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Interstate Highway System

Interstate Highway System

The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly called the Interstate Highway System, is a network of highways in the United States. The Interstate Highway System is a separate system within the larger National Highway System. With very few exceptions, Interstate highways are controlled-access freeways, allowing for safe high-speed driving when traffic permits. They are assigned a special level of funding at the federal level. Despite this federal funding, these highways are owned, designed, built and maintained by the state in which they are located, with the only exception being the federally-owned Woodrow Wilson Bridge on the Capital Beltway (I-95/I-495). The highways in the system are typically known as Interstate XX or I-XX; sometimes Interstate Highway XX (IH XX) or Interstate Route XX (IR XX) is used. In some areas the more generic Route XX or Highway XX is used. The system serves all major U.S. cities, and unlike its counterparts in most industrialized countries, often goes right through downtown areas rather than bypassing them. This facilitated the emergence of automobile-oriented postwar suburban development patterns, often pejoratively referred to as "urban sprawl". The system is prominent in the daily lives of most Americans. Virtually all goods and services are delivered via the Interstate Highways at some point. Many residents of American cities use the urban segments of the system to go to and from their jobs. Most long-distance journeys (for vacation or business) of less than 300 miles (500 km) use the interstate highway system at some point. Hawaii has several signed Interstates, but Alaska and Puerto Rico do not. The latter two do have roads designated as Interstates for funding purposes, but they are not currently or planned to be built to Interstate standards. The public controlled-access highways of Puerto Rico are the Autopistas (PR-22, PR-52, and PR-53).

History

Autopistas The interstate system was authorized by the Federal-Aid Highway Act of 1956, popularly known as the National Interstate and Defense Highways Act of 1956. It was lobbied for by major U.S. automobile manufacturers and championed by President Dwight D. Eisenhower, and was influenced by both his experiences as a young soldier crossing the country in 1919 following the route of the Lincoln Highway, and by his appreciation of the German autobahn network. Planning for a system of new superhighways began in the late 1930s, even before federal commitment to build the Interstate highway system came in the 1950s. Construction on the world's first public limited-access highway, the Bronx River Parkway, had begun in New York as early as 1907. By the 1920s, longer highways such as the New York City parkway system had been built as part of local or state highway systems. As automotive traffic increased, planners saw a need for such an interconnected national system to supplement the existing, largely non-freeway, U.S. Highway system.The General location of national system of interstate highways, including all additional routes at urban areas designated in September, 1955 maps what became the interstate system, and is informally known as the Yellow Book. Although construction on the Interstate Highway system continues, it was officially regarded as complete in 1991 (though 1.5 miles of the original planned system remain unconstructed as of 2005 [http://www.fhwa.dot.gov/programadmin/interstate.html]). The initial cost estimate for the system was $25 billion over twelve years; it ended up costing $114 billion, taking 35 years to complete. As of 2004, the system contains over 42,700 miles (68,500 km) of roads, all at least four lanes wide.

Standards

:Main article: Interstate Highway standards The American Association of State Highway and Transportation Officials (AASHTO) has defined a set of standards that all new Interstates must meet unless a waiver from the Federal Highway Administration (FHWA) is obtained. These standards have become stricter over the years. One almost absolute standard is the controlled access nature of the roads. Except for a few exceptions, traffic lights (and cross traffic in general) are limited to toll booths and ramp meters (metered flow control for lane merging during rush hours).

Speed limits

Speed limits vary according to location. By initial planning, the Interstate system was designed to provide reasonable road safety at speeds of 75 to 80 miles per hour (120 to 130 km/h) except in limited stretches (such as steep mountain passes or urban cores) where many vehicles cannot maintain such speeds. Many western states had high speed limits. Kansas, for example, had a posted limit of 80 mph (130 km/h)[http://people.smu.edu/acambre/blog/PermaLink,guid,5575625c-bbd4-47a3-be9f-9d5517d3a06f.aspx]. Some states, such as Oregon, defined the limit as whatever was "reasonable and proper", which would not be allowed today (see Montana reference below). In 1974, the federal government enacted 55 mph (90 km/h) as a gasoline conservation measure in response to the 1973 energy crisis. After the end of the embargo this restriction was continued as a safety measure. It was very unpopular, especially in western states. The 55 mph cap was relaxed in 1987 to allow 65 mph (105 km/h) speeds on rural Interstates if the states so chose. During this interim period, some roads (such as I-335 in Kansas) were specifically designated as Interstates to take advantage of this higher speed limit. Shortly thereafter, 65 mph limits were allowed on roads not numbered as interstates but which were built to interstate standards. The 55/65 mph caps were eliminated in late 1995, fully returning speed limit control to the states. Many states maintain several different limits. For example, in California, most interstates are limited to 55 mph within a major city, 65 mph (105 km/h) for most of the suburban highway stretches, and up to 70 mph (115 km/h) throughout the desert and rural stretches of the state. In some states, commercial trucks have a lower speed limit than passenger automobiles. In some mountainous regions, the condition of the roadway mandates a lower speed limit than would otherwise have applied. While some states have maintained the 65 mph limit, other states have increased the limits to 70 or 75 mph (110 or 120 km/h). Generally, the highest speed limits are found in the South and Southwest, while the lowest are found in the Northeast. Soon after the end of the National Maximum Speed Limit, the state of Montana ended daytime speed limits for automobile traffic on Interstate Highways in the state, instead instructing motorists to maintain a "reasonable and prudent" speed. A few years later, the "reasonable and prudent" law was declared unconstitutional for being too vague and a limit of 75 mph (120 km/h) was enacted in its place. Texas recently enacted a law allowing 80 MPH speed limits on certain portions of Interstates 10 and 20 in far west Texas. However, these limits are on hold pending further study by the Texas Department of Transportation.

Dual-purpose design

In addition to being designed to support automobile and heavy truck traffic, interstate highways are also designed for use in military and civil defense operations within the United States, particularly troop movements. One potential civil defense use of the Interstate Highway System is for the emergency evacuation of cities in the event of a potential nuclear war. Although this use has never happened, the Interstate Highway System has been used to facilitate evacuations in the face of hurricanes and other natural disasters. An option for maximizing throughput is to reverse the flow of traffic on one side so that all lanes become outbound lanes. This procedure is known as Contraflow, and could be seen in the evacuations of New Orleans, Louisiana and Houston, Texas prior to hurricanes Katrina and Rita, respectively. Several Interstates in the South, including I-16 in Georgia, I-40 in North Carolina, I-65 in Alabama, I-10 & I-59 in Louisiana, and I-59 in Mississippi, are equipped and signed specifically for contraflow, with crossovers inland after major interchanges to distribute much of the traffic. This is however not limited to Interstates; US 49 from Gulfport to Jackson and State Road 528, in Central Florida, have the same setup. A widespread but false urban legend states that one out of every five miles of the Interstate highway system must be built straight and flat, so as to be usable by aircraft during times of war.[http://www.tfhrc.gov/pubrds/mayjun00/onemileinfive.htm] However, the Germans in World War II used the Autobahns for just such a purpose.

Terminology

While the name implies that these highways cross state lines, many Interstates do not. Rather, it is the system of interstates that connects states. There are interstate highways in Hawaii, funded in the same way as in the other states, but entirely within the populous island of Oahu. They have the designation of H-X, and connect military bases. Similarly, both Alaska and Puerto Rico have public roads that receive funding from the Interstate program, though these routes are not signed as Interstate Highways.

Primary routes

The numbering scheme for the Interstate Highway System (as well as the U.S. Highway System) is coordinated by the American Association of State Highway and Transportation Officials (AASHTO), though their authority is occasionally trumped by a number written into Federal law. Within the continental United States, primary Interstates (also called main line Interstates or two-digit Interstates) are given one- or two-digit route numbers. Most Interstates have two numbers; there are only three one-digit Interstates in the system: I-4, I-5 and I-8. Within this category, east-west highways are assigned even numbers, and north-south highways are assigned odd-numbers. Odd route numbers increase from west to east, and even numbered routes increase from south to north. Numbers divisible by 5 are intended to be primary routes, carrying traffic long distances. For example, I-5 runs from Canada to Mexico along the west coast (the only interstate to do so) while I-95 runs from Miami north to Canada. In addition, I-10 runs from Los Angeles, California to Jacksonville, Florida while I-90 runs from Seattle to Boston. However, not all primary routes traverse long distances. I-45 runs from Galveston, Texas north to Dallas, Texas, a distance of only 284 miles. It is the only primary route that does not cross state lines (see List of intrastate Interstate Highways). It should be noted that I-50 and I-60 do not exist (and there are no even-numbered Interstates between 46 and 62), mainly because they would most likely have passed through the same states that already have US 50 and US 60. AASHTO rules discourage Interstate and US Highways with the same number to exist in the same state, although I-24 and US 24 exist at opposite ends of Illinois. Some planned Interstates do not follow this guideline - I-69 will enter Texas (which has US 69), I-74 will have a multiplex with US 74 in North Carolina, and I-41 will do the same with US 41 in Wisconsin. Several two-digit numbers are shared between two roads at opposite ends of the country, namely I-76, I-84, I-86 and I-88. Some of these were the result of a change in the numbering system in the 1970s; previously letter-suffixed numbers were used for long spurs off primary routes; for example, western I-84 was I-80N, as it went north from I-80. In the 1970s, AASHTO decided to eliminate these; some became additional two-digit routes, while others became three-digit routes (see below). Only two pairs of these exist; I-35 splits into I-35W and I-35E through both the Dallas-Fort Worth and the Minneapolis-St. Paul areas. Strict adherence to the directional nature of the system results in some amusing oddities. For a ten-mile stretch east of Wytheville, Virginia, the driver can be traveling on both North I-81 and South I-77 at the same time (and vice versa) (see also Wrong-way multiplex). For the sake of efficiency, some Interstates double up for short or sometimes long distances, as in the example above. Another notable example are Interstates I-90 and I-94, which double and then separate several times as they criss-cross the upper Midwest and Great Plains.

Three-digit Interstates

Three-digit route numbers, consisting of a single digit prefixed to the number of a primary Interstate highway, are used to designate usually short spur or loop routes from their "parent" route, either directly or via another three-digit Interstate. A route that spurs from its parent and ends at an intersection with no other Interstates is given an odd first digit; a route that returns to its parent is given an even first digit. The number given to the first digit of a route that spurs from the parent and ends at another Interstate depends on the state; some consider these routes spurs and give them odd numbers, while others consider them loop-style connectors and give them even numbers. For instance, I-90 in New York has a full set of three-digit Interstates - I-190, I-290, I-390, I-490, I-590, I-690, I-790, I-890 and I-990. Due to the large number of these routes, they can be repeated in different places along the mainline; no two three-digit Interstates in the same state can share a number. The Minneapolis-St. Paul area has a single loop around the entire Metro area. I-94 intersects the loop in two spots and runs directly through it separating it into a northern and southern half. The southern half of it is labeled I-494 while the northern half of it is labeled I-694. Charlotte, North Carolina has a single loop around the city that intersects with both I-77 and I-85, but the entire loop is known as I-485. The Baltimore-Washington metropolitan area has several spur routes off of I-95. The area has I-195, I-295, I-495, I-795 and I-895. It also has two routes numbered I-395 (in Baltimore and Washington) and two I-695s (one is signed, the other is a secret designation), as well as an unsigned route called I-595. No I-995 exists anywhere. New York City has numerous spur routes off of I-78 and I-95, but none of I-78's spur routes actually intersect with I-78. A three-digit spur off a letter-suffixed two-digit Interstate (see above) was given a number without a letter suffix, except for one case - I-184 in Idaho was I-180N.

Exceptions

:Main article: List of gaps in Interstate Highways Interstate 238 near Oakland, California is one of two major exceptions to the numbering scheme, as no Interstate 38 exists. This number exists because Interstate 238 replaced a segment of California Highway 238, and no appropriate number was available. The other exception is I-99 in Pennsylvania, which was written into law as I-99 by Pennsylvania Congressman Bud Shuster; I-99 (which is also U.S. Highway 220) is west of several Interstates that are numerically less than 99, and was the nearest available unused two-digit number. Some proposed future Interstate routes have been given similarly non-conforming designations by their legislative proponents. For example, backers of the proposed Third Infantry Division Highway, a route in Georgia and Tennessee, have suggested it be named Interstate 3, in honor of the division for which the highway is named [http://www.interstate-guide.com/i-003.html].

Other notable examples

- I-82 lies fully north of I-84, but I-84 was I-80N when I-82 got its number.
- I-85 diverts west of I-75 (intersecting it near Atlanta, Georgia) The following two-digit Interstates change signed direction from their normal (even=east-west, odd=north-south) direction:
- I-69
- I-76 (west) Two-digit interstates in Hawaii, as well as the "paper" interstates of Alaska and Puerto Rico, are numbered sequentially in order of funding, without regard to the rules on odd and even numbers. Business Loop and Business Spur Interstates are not subject to any of the Interstate standards. Their designation is simple - a Business Loop heads into a downtown area from its parent and returns to its parent; a Business Spur ends downtown, occasionally continuing from the end of the main Interstate. Business routes can split from either two- or three-digit Interstates, and can be repeated within a state. In a few cases, where an Interstate has been realigned, the old road has been designated a Business Loop because it is not up to standards.

Financing

About 72% ([http://www.fhwa.dot.gov/policy/ohim/hs03/htm/hf10.htm 2003 FHWA summary]) of the construction and maintenance costs are funded through user fees, primarily gasoline taxes, collected by states and the federal government, and tolls collected on toll roads and bridges. The rest of the costs come out of the federal budget. In the eastern United States, large sections of some Interstate Highways planned or built prior to 1956 are operated as toll roads. The taxes dedicated to the construction and maintenance of highways are often criticized as a direct subsidy from the government to promote and maintain auto-oriented development as we know it today. The dominant role of the federal government in road finance has enabled it to pass laws in areas outside of the powers enumerated in the federal Constitution. By threatening to withhold highway funds, the federal government has been able to force state legislatures to pass a variety of laws. Examples include increasing the legal drinking age to 21, for a number of years reducing the maximum speed limit to 55 miles per hour, passing Megan's Law legislation, lowering the legal intoxication level to 0.08/1000, and other laws. This has proved to be controversial. Those who support this feel that it is a way to provide an impetus to states to pass uniform legislation. Others feel that using highway dollars in this fashion upsets the balance between federal and states' rights in favor of the federal government, and effectively holds funds as ransom in order to coerce state governments into passing laws that would not have otherwised been introduced. As American suburbs push ever outward, the costs incurred of maintaining freeway infrastructure has started to catch up with the economy, leaving little in the way of funds for new interstate construction. This has led to the proliferation of the toll road (turnpike) as the new method of building limited-access highways in suburban areas. Also, some interstates are being privately maintained now (VMS in Texas, I-35) in order to cut rising costs of maintenance and allow state departments of transportation to focus on serving the fastest growing regions in their respective states. The future of the interstate system as we know it is in question. It is entirely possible that parts of the system will have to be tolled in the future to meet maintenance and expansion demands, as is done with adding toll HOV/HOT lanes in certain cities like Minneapolis, Houston, Dallas, and Washington D.C.

Non-chargeable Interstate routes

In addition to Interstate highways financed with federal funds (Chargeable Interstate routes), federal laws allow other highways to be signed as Interstates, if they meet the Interstate Highway standards and that they are logical additions or connections to the System. Called Non-Chargeable Interstate routes, these additions fall under two categories: # Routes that already meet Interstate standards. They can immediately be signed as Interstates once their proposed number is approved. # Routes designated as a future part of the system once they are upgraded to Interstate standards. Until then, it cannot be signed as an Interstate yet.

Signage

dollar Interstate Highways are signed by a number on a red, white and blue sign as shown to the right. In the original design, the state was formerly listed above the highway number, but in many states, this area is now left blank. The sign itself measures 36 inches high, and is 36 inches wide for two-digit interstates, or 45 inches for three-digit interstates. Business Loop and Business Spur Interstates use a special shield where the red and blue are replaced with green; the word BUSINESS appears instead of INTERSTATE, and the word SPUR or LOOP usually appears above the number. The majority of Interstates have exit numbers. All traffic signs and lane markings on the Interstates are supposed to be designed in compliance with the Manual on Uniform Traffic Control Devices (MUTCD). However, there are many local and regional variations in signage. The state of California is now adapting to an exit numbering system after many years as being the only state in the country that did not use such a system. In most states, the exit numbers correspond to the mileage markers on the Interstates (with an exception being I-19 in Arizona, whose length is measured in kilometers instead of miles). Many northeastern states label exit numbers sequentially, regardless of how many miles have passed between exits. On even-numbered Interstates, mileage increases to the east and decreases to the west; and on odd-numbered Interstates, mileage increases to the north and decreases to the south. In both cases, the exit numbers increase and decrease accordingly.

Interstate oddities

- Vinita, Oklahoma — A McDonalds is built over the top of Interstate 44. It goes from one side of the interstate to the other, passing over the interstate. Customers can sit inside and eat while traffic drives beneath them. It is also purported to be the "world's largest".
- Kearney, Nebraska — The Great Platte River Road Archway Museum is built over top of Interstate 80. The 1,500 ton structure spans 308 feet across the interstate and houses a museum dedicated to frontier culture.
- Reno, Nevada — A Walgreens store sits on top of a segment of Interstate 80 in downtown Reno.
- Newton, Massachusetts — A Star Market supermarket is built over the top of Interstate 90. Traffic reporters refer to this point on the highway as the "Star Market overpass".
- Newton, Massachusetts — A Sheraton hotel is built over the top of Interstate 90.
- Boston, Massachusetts — The Prudential Tower in downtown Boston is built over top of Interstate 90 as well. A less known fact about Interstate 90 is that it is built over what used to be the largest railroad corridor in New England; photos from the 1950s show huge rail yards where I-90 now comes into the city. Many of the oddities on I-90 are the result of deals struck by the Massachusetts Turnpike Authority, Perini Corporation (which constructed the majority of the highway), and existing buildings at the time of construction. In return for not obstructing the highway project, the MTA went to lengths such as preserving the aforementioned Star Market.
- Atlanta, Georgia — The Civic Center MARTA station is located over the Downtown Connector (Interstate 75/85) at West Peachtree Street, making it the only subway station built over an Interstate highway.
- Illinois — The Illinois Tollway oasis is a type of rest area which spans the top of the interstate highway it is on. There are seven of them which are on the Tri-State Tollway (Interstates 80, 94 & 294), Northwest Tollway (Interstate 90) and the Ronald Reagan Memorial Tollway (Interstate 88). Customers are able to sit inside the Oases and eat while traffic goes by beneath them. This type of development is common in the UK.
- Seattle, Washington — The [http://www.ci.seattle.wa.us/parks/parkspaces/FreewayPark.htm Seattle Freeway Park] sits on top of Interstate 5 (NB and SB, including HOV express lanes). The park is connected to the [http://www.wsctc.com Washington State Convention Center] connecting downtown to the [http://www.ci.seattle.wa.us/tour/capitol.htm Capitol Hill] and First Hill districts (locally, First Hill is also known as "Pill Hill" as this is Seattle's medical district). The park is multi-level and as such, there are areas where visitors are able to watch traffic pass by.
- Breezewood, Pennsylvania — There is a sign of a policeman pointing at you saying, "You! Slow Down!" You then have to drive a few blocks on US 30 before returning to I-70. This is a rare instance of a traffic light on an interstate.
- Jersey City, New Jersey — Interstate 78 follows a pair of one-way streets for a short distance between the Newark Bay Extension of the New Jersey Turnpike and the Holland Tunnel, which leads into New York City. Along with the aforementioned I-70, this is the only other primary interstate with traffic lights.

Criticism

In addition to the various economic issues, the system has roused criticism on aesthetic grounds. The efficiency and faster speeds of the system, made possible in part by engineering techniques that often tend to cut through the land rather than merely following it as with the older U.S. Highway, have inevitably resulted in a safer but less-scenic drive. When the cross-country I-40 was finally finished in the late 1980s, by completing the segment between Raleigh, North Carolina and Wilmington, North Carolina, Charles Kuralt stated, "It is now possible to travel from coast to coast without seeing anything!"

References

# 65 MPH Approved for Route, Wichita Eagle-Beacon, October 24, 1987 # Field, David. "On 40th birthday, interstates face expensive midlife crisis." Insight on the News, 29 July 1996, 40-42.

External links

- [http://www.fhwa.dot.gov/programadmin/interstate.html Interstate Highway information]
- [http://www.fhwa.dot.gov/reports/routefinder/index.htm FHWA Route Log and Finder List]
- [http://www.tfhrc.gov/pubrds/septoct00/urban.htm FHWA Turner-Fairbank Highway Research Center] - Analysis and History of Interstate Highway System
- [http://www.kurumi.com/roads/3di/ 3-digit Interstate Highways]
- [http://www.aaroads.com/ Pictures of all Interstates]
- [http://www.ourdocuments.gov/doc.php?doc=88 One] of 100 milestone documents of American history
- Federal Highway Administration's [http://www.tfhrc.gov/pubrds/summer96/p96su10.htm article on the act]
- Fortune magazine on [http://www.fortune.com/fortune/fortune500/articles/0,15114,574088,00.html history of the Interstate Highway System]
- [http://www.geocities.com/michelleskinnerfreeway Another great Interstate Page], with facts on all 2-digit Interstates and links to their exit lists
- [http://www.ajfroggie.com/triskele Highway Heaven] Contains exit lists for most Interstate highways
- [http://www.triskele.com/fonts/index.html RoadGeek] - A complete set of TrueType fonts for simulating Interstate and other highway signage ja:ドワイト・デーヴィッド・アイゼンハワー全米州間国防高速道路網

Highway

:For other uses, see Highway (disambiguation). A highway is a major road within a city, or linking several cities together. It includes roads known as interstate highway, freeway, motorway and autobahn, where a full description varies by country. Generally, a highway is a road which has multiple lanes of traffic in each direction, often with a physical division (median) between opposing traffic, and separate access ramps to and from the highway which are more widely separated than connections on a standard road and are often grade-separated. A highway may prohibit access by pedestrians and limit what vehicles may travel on it. Historically, a highway was any major road travelling a long distance outside of a city. Early roads between cities would sometimes suffer from highwaymen who would rob people travelling the route. In the 20th century, however, the word generally came to be used only for high-speed, often specially-designed automobile routes. On 10 September, 1913 the first paved coast-to-coast highway opened in the US. Highways usually have a higher speed limit than other roads because they have additional lanes and are designed for driving at a higher speed. In remote areas, a highway may have rest areas where motorists may stop and relax before resuming a long drive. By convention, the lane nearest the median on a multi-lane highway is called the passing lane. The United States has a vast network of national highways (Interstate highways) linking the different U.S. states together, as does Australia albeit on a much smaller scale and mostly concentrated on the southeast coastline. Some highways, like the Pan-American Highway or the European routes, bridge multiple countries. With the latter a single road may have several national designations in addition to the European one. Probably the most famous highway in the United States is Route 66, as immortalised in the song "(Get Your Kicks On) Route 66", while if one follows Australia's Highway 1 the driver can travel from state capital to state capital, almost the entire way around the whole country. The longest single national highway in the world is the Trans Canada Highway, which runs from Victoria, British Columbia, on the Pacific Coast, through ten provinces to the Atlantic Coast, at St. John's, Newfoundland.

Nomenclature

The terms used for various types of highways such as freeway, expressway, motorway and autobahn, vary between countries or even regions within a country. In some places a highway is a specific type of major road that is distinct from freeway or expressway; in other places the terms may overlap. In law highway may mean any public road or canal. However, in some countries, the term highway is not generally used at all.

Australia

In Australia, a highway is a distinct type of road from freeways and motorways. The word highway is generally used to mean major roads connecting large cities, towns and different parts of metropolitan areas. Metropolitan highways often have traffic lights at intersections, and rural highways usually have only one lane in each direction. The words freeway or motorway are generally reserved for the most arterial routes, almost always with no traffic light intersections and usually significantly straightened and widened. The term motorway is used in some Australian cities to refer to freeways that have been allocated a metropolitan route number, and in Sydney, a motorway has a toll, whereas a freeway is free of charge. It is now possible to travel from Melbourne to Sydney without having to stop at a traffic light. Roads may be part-highway and part-freeway until they are fully upgraded.

New Zealand

In New Zealand, a motorway runs through urban areas and an expressway runs through rural areas. Both motorways and expressways generally have no access to adjacent properties and no facility for pedestrians or cyclists. New Zealand's main routes are designated state highways. State Highway 1 is the only route to run through both the North and South Islands, and runs (in order north-south) from Cape Reinga to Wellington in the North Island, and from Picton to Bluff in the South Island. State Highways 2-5 are main routes in the North Island, State Highways 6-9 in the South Island, and state highways numbered from 10 onwards are generally found in numerical order from north to south. State highways usually incorporate different types of roads, for example, State Highway 1 from Auckland to Hamilton incorporates the Northern and Southern Motorways in the Auckland area, the Waikato Expressway, and a rural road before passing through the streets of Hamilton. The term freeway is rarely used relating to New Zealand roads, and can only be considered an Americanism.

Brazil

In Brazil, highways (or expressway/freeway) are named "rodovia", and Brazilian highways are divided in two types: regional highways (generally of less importance and entirely inside of one state) and national highways (of major importance to the country). In Brazil, rodovia is the name given exclusively to roads connecting two or more cities with a sizable distance separating the extremes of the highway. Urban highways for commuting are uncommon in Brazil, and when they are present, they receive different names, depending of the region (Avenida, Marginal, Linha, Via, Eixo, etc). Very rarely names other than "rodovia" are used. Regional highways are named YY-XXX, where YY is the abbreviation of the state where the highway is running in and XXX is a number (e.g. SP-280; where SP means that the highway is running entirely in the state of São Paulo). National highways are named BR-XXX. National highways connects multiples states altogether, are of major importance to the national economy and/or connects Brazil to another country. The meaning of the numbers are:
- 001-100 - it means that the highway runs radially from Brasília. It is an exception to the cases below.
- 101-200 - it means that the highway runs in a south-north way.
- 201-300 - it means that the highway runs in a west-east way
- 301-400 - it means that the highway runs in a diagonal way (northwest-southeast, for example)
- 400-499 - another exception, they are less important highways and its function is to connect a city to an arterial highway nearby Often Brazilian highways receives names (famous people, etc), but even though, they continue to have a YY/BR-XXX name (example: Rodovia Castelo Branco is also SP-280). See List of Brazilian Highways

Canada

- In Canada, there is no national standard for nomenclature, although highway appears more popular in all areas except
- Ontario: highways are called expressway or 400-Series; 401 in Toronto is a freeway. The DVP (Don Valley)is a parkway. All provincial managed highways are called King's Highways. Highway 407 is a toll route.
- Quebec where highways are called autoroutes (borrowing the term from French).
- Nova Scotia numbers its freeways by the routes they parallel, for example, Highway 101 parallels Trunk 1.
- The Trans Canada Highway, the highway (mostly four lane, sometimes less, sometime more) that crosses the entire country (and entering all ten provinces), holds the record as the longest national highway in the world. The only portions of this road not considered to be of freeway status are in the British Columbia Rocky Mountains, Northern Ontario, and in Newfoundland.

China

"Highways" in China, more often than not, refer to China National Highways. The multi-lane, central-separation routes are instead called expressways. In Mainland China, private companies reimbursed through tolls are the primary means of creating and financing the National Trunk Highway System. There is actually no separate classification for expressway (which is the term more often used in the PRC). Most likely, they are lumped with first-grade guodaos (meaning National roads). Beneath guodaos in rank level are shengdaos (provincial roads) and xiandaos (pronounced hsien-daos or shien-daos, which equate to county-level roads). Some expressways are numbered with a leading zero (e.g. G030). Freeway was used on a few expressways (such as the Jingshi Freeway) before expressway was chosen as a standarised term. The Chinese name for expressways (or freeways, as they used to be called) is uniform; in pinyin, it is gao su gong lu, which literally means "high speed public road". In the mainland of the PRC, highway does not refer to a freeway or expressway, but instead to a normal road equivalent to an "A"-level road in Britain, or a class-one non-expressway. This can cause some confusion, though. public road, New Territories, Hong Kong.]]

Hong Kong

In Hong Kong, the type of high speed roads is referred to as expressway, but some are named as highways or roads ('Yuen Long Highway', 'Tolo Highway', 'Tsuen Wan Road', 'Tuen Mun Road', etc.). Some others are named corridors and bypasses.

India

Main article Indian highways In India, 'Highway' refers to one of the many National Highways that run up to a total length of about 58000 kilometers. An expressway refers to any elevated road with grade-separated intersections.

Malaysia

The highest level of major roads in Malaysia, expressway (lebuhraya), has full access control, grade separated junctions, and mostly tolled. The expressways link the major state capitals in Peninsular Malaysia and major cities in Klang Valley. Highway is lower level with limited access control, some at-grade junctions or roundabouts, and generally with 2 lanes in each separated direction. These are generally untolled and funded by the federal government, hence the first one is called Federal Highway linking Klang and Kuala Lumpur. The trunk roads linking major cities and towns in the country are called federal trunk roads, and are generally 2 lanes single carriageway roads, in places with a third climbing lane for slow lorries.

South Africa

Colloquially, the terms "freeway," "highway," and "motorway" are used synonymously. There are very few references to the term "expressway" in South Africa. A freeway, highway or motorway refers to a divided dual carriageway with limited access/egress, with at least two lanes in either direction. A central island, usually either with drainage, foliage or high-impact barriers, provides a visible separation between carriageways in opposite directions. As with the UK and Australia, South Africans drive on the left-hand side of the road and all steering wheels are on the right-hand side of vehicles. Freeways are designated with one of three labels: N (in reference to national roads), R (short for "route," in reference to provincial roads), and M (in reference to metropolitan roads). This has more to do with the location of a road and its function than anything else. In addition, "N" roads usually run the length of the country over long distances, "R" roads usually inter-connect cities and towns within a province, and "M" roads carry heavy traffic in metropolitan areas. Route markings also determine who paid for the road: "N" was paid for by national government, "R" by provincial government and "M" by local government. In recent years, some "R" roads have been re-designated as "N" roads, so that control and funding comes from the South African National Roads Agency.

Switzerland

The term Autobahn is used for normal expressways where there is a central physical structure separating two different directional carriageways. This is often translated into English as motorway. In express routes where there is no central physical structure separating two different directional carriageways, but crossings are still motorway-like otherwise, and traffic lights are not present, the road is instead called an Autostrasse, translated into English as a motorroad. Autostrassen often have a lower speed limit than Autobahnen. See also: Lists of Autobahns

Great Britain and Ireland

In Great Britain and Ireland, unless a route is classified as a motorway, the term used may be main road, trunk road, 'N' road/'R' road (In Ireland), 'A' road/'B' road (In The UK), or, where appropriate, dual carriageway. In the law of England and Wales the term highway covers everything from a footpath (for foot passage only), to a bridleway (for foot, bicycle and equestrian use), to a byway open for all traffic (for all the aforementioned users, plus any motorised user), to unclassified county roads, classified roads, trunk roads, motorways and special roads. In British law, there is no definition of "road", and generally the most common usage refers to: bridleway
- "Carriageway",
- "Footpath",
- "Bridleway" or
- "Byway" In England and Wales the public are said to have a "right of way" over a Highway. This means that, subject to statutory restrictions, the route must be kept clear to allow travel by anyone who wishes to it. At common law, it is forbidden to obstruct a highway or interfere with passage. However, many statutory provisions provide powers to do so (for instance to carry out road works). Rights of way exist both over roads maintained at the public expense (the majority of roads) and over some roads on private property. In this case, the owner must allow passage over the highway. A right of way may be created by custom (i.e. the road has been used for a long period of time) or under the relevant positions of the Highways Act 1980. A right of way may by only be extinguished or diverted by or under an Act of Parliament. For instance, under the Channel Tunnel Rail Link Act 1996 authority is given for the builder of the rail link to stop up certain highways mentioned in Schedule 3 of the act. The contrast to a Highway is a private road over which no right of way exists. Travel on a private road is subject to the consent of the owner of the land.

United States

In the U.S., the terms expressway and freeway are legally defined by federal regulation and under the laws of most U.S. states according to civil engineering usage. However, the distinction between these two terms is not universal, and in several states which built freeways very early on (including Connecticut, Illinois, New Jersey, New York, and Pennsylvania), the terms expressway and freeway have the same meaning. In those states, expressway, the older usage, is often preferred. In New Jersey and Pennsylvania, newer roads are often officially styled freeways, where older roads retain the title "expressway". In New England and New York, the term freeway is rarely if ever used; highway is the generic term for high-speed limited-access roads, though Expressway and Freeway are both used as part of the proper name of some roads. In the rest of the country, freeway is the usual term; however, the distinction between freeways and highways is not always as clear or well-understood as it is in California, which has many of both kinds of highway. In California, freeways are divided, grade-separated, controlled-access highways where private driveways, pedestrians, and bicyclists are forbidden, where speed limits range from 55 to 70 miles per hour, and are usually elevated within major cities. Highways are divided, but may have at-grade or grade-separated intersections as demand requires, private driveways are minimized (but not completely forbidden), bicyclists and pedestrians are sometimes allowed, and the speed limits range from 45 to 55 miles per hour. Within a major city a highway can have commercial buildings along it. All interstate highway routes in California are freeways, most important intracity state routes are freeways, and most important intercity state routes are highways (with sections being upgraded to freeways as necessary). In the U.S., particularly in statutes, the term highway technically has the broader meaning than that given at the beginning of this article (encompassing all state government-maintained roads or canals for cross-city or inter-city traffic), but in colloquial usage is often used to refer only the subset of that category that includes roads less important than a freeway. That subset generally includes roads with 2, 4, or 6 lanes, with or without a center divider, that have at-grade intersections and driveways connecting to adjacent properties. However, even then, such highways are usually built to higher standards (wider lanes and more durable pavement) than the connecting arterial routes, streets, alleys, and driveways. The highest continuous road in the United States is the Trail Ridge Road that runs through the Rocky Mountain National Park in Colorado. The term highway is also often used in colloquial speech where the correct term would be "State Route," or "U.S. Route." For example, California residents frequently refer to Highway 101 rather than U.S. 101.

Further information

For information on the history and local styles of highways around the world refer to
- Auto-Estrada (Portugal)
- Autopista (Spain)
- Autoroute (France)
- Autoroute (Quebec)
- Autobahn (Germany)
- Autostrada (Italy)
- Highways (India)
- Expressway (Mainland China)
- Expressway (Lebuhraya) (Malaysia)
- Freeway, Expressway, and Parkway (United States)
- Freeway (Canada)
- Motorway (United Kingdom)
- Motorway (Ireland)
- National Trunk Highway System (Mainland China)
- Rodovia (Brazil)

External link

- [http://dictionary.law.com/default2.asp?typed=highway&type=1&submit1.x=63&submit1.y=16&submit1=Look+up Legal definition in the U.S.]
- [http://www.us-highways.com/ U.S. Highways: From US 1 to (US 830)]
- [http://www.milebymile.com/ Mile By Mile U.S. Highway Travel Information Guides]
- [http://www.elbruz.org/eroads/AGR_2.htm Full list of Euroroutes with distances] Category:Road infrastructure Category:Road transport ja:高速道路 ms:Lebuhraya

National Highway System

Note: This article was adapted from public domain Federal Highway Administration web sites. The National Highway System comprises approximately 160,000 miles (256,000 kilometers) of roadway important to the nation's economy, defense, and mobility. The National Highway System (NHS) includes the Interstate Highway System as well as other roads important to the nation's economy, defense, and mobility. The NHS was developed by the United States Department of Transportation (DOT) in cooperation with the states, local officials, and metropolitan planning organizations (MPOs).

Components of the National Highway System

The National Highway System (NHS) includes the following subsystems of roadways (note that a specific highway route may be on more than one subsystem): Interstate - The Eisenhower Interstate System of highways retains its separate identity within the NHS. Other Principal Arterials - These are highways in rural and urban areas which provide access between an arterial and a major port, airport, public transportation facility, or other intermodal transportation facility. Strategic Highway Network (STRAHNET) - This is a network of highways which are important to the United States' strategic defense policy and which provide defense access, continuity and emergency capabilities for defense purposes. Major Strategic Highway Network Connectors - These are highways which provide access between major military installations and highways which are part of the Strategic Highway Network. Intermodal Connectors - These highways provide access between major intermodal facilities and the other four subsystems making up the National Highway System .

Purpose

The purpose of the National Highway System is to extend the benefits of the Interstate Highway System to areas that are not served directly by it

Status

About 98 percent of all roads in NHS have been built. The 256,000 kilometers (km) of NHS include only 4 percent of the nation's roads, but they carry more than 40 percent of all highway traffic, 75 percent of heavy truck traffic, and 90 percent of tourist traffic.

History and justification

In 1995, Congress approved NHS. Although the landmark Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA) provided that certain key routes, such as the Interstate Highway System, be included in NHS, most of NHS was not specified. The Federal Highway Administration worked closely with our state and local partners, such as transportation departments and metropolitan planning organizations, to identify key routes. They, after all, know best how their roads function and how these roads fit into their overall transportation plans. The NHS is not another system of interstate highways. In fact, beyond the interstate segment, NHS consists mostly of existing two-lane roads, and about 98 percent of all roads in NHS have already been built. Yet these roads are vital. The 256,000 kilometers (km) of NHS include only 4 percent of the nation's roads, but they carry more than 40 percent of all highway traffic, 75 percent of heavy truck traffic, and 90 percent of tourist traffic. The advantage of NHS is that it encourages states to focus on a limited number of high-priority routes and to concentrate on improving them with federal-aid funds. At the same time, the states can incorporate design and construction improvements that address their traffic needs safely and efficiently. With NHS, states can choose from a range of improvements. They can make operational changes, such as a program to locate and remove stalled vehicles that are impeding smooth traffic flow. States can employ available technological improvements, such as Intelligent Transportation Systems (ITS), which will help reduce congestion and keep traffic moving without major, roadway expansion. NHS also will help us meet the challenges of global economic competititon by enhancing our different modes of transportation, increasing America's productivity, and bolstering its economy. It is a unified system with each mode complementing the others. Increasingly, intermodal carriers rely on all forms of transportation to deliver goods and services to consumers in the most efficient manner possible. NHS fulfills that goal by serving 198 ports, 207 airports, 67 Amtrak stations, 190 rail/truck terminals, 82 intercity bus terminals, 307 public transit stations, 37 ferry terminals, 58 pipeline terminals, and 20 multipurpose passenger terminals. By providing these essential linkages to other modes, NHS creates a seamless transportation system for the rapid movement of people and products. NHS reaches virtually every part of the country. About 90 percent of America's population lives within 8 km of an NHS road. All urban areas with a population of more than 50,000 and 93 percent with a population of between 5,000 and 50,000 are within 8 km of an NHS road. Counties that contain NHS highways also host 99 percent of all jobs in the nation, including 99 percent of manufacturing jobs, 97 percent of mining jobs, and 93 percent of agricultural jobs.

References

- [http://www.fhwa.dot.gov/hep10/nhs/ National Highway System]
- [http://www.tfhrc.gov/pubrds/spring96/p96sp2.htm Slater, Rodney E., 1996, The National Highway System: A Committment To America's Future, Public Roads, Spring, Vol. 59, No. 4.] Category: Transportation in the United States Category: United States Highway system

List of gaps in Interstate Highways

For the most part, the United States Interstate Highway System is a connected system, with most roads completed. However, some Interstates have gaps. There are several cases covered here:
- True gaps, where two sections of road are intended to be part of the same Interstate, but the two sections are not physically connected, or are only connected by non-Interstates, or are connected but the connection is not signed as part of the highway
- Freeway gaps, where the Interstate is signed as a continuous route, but part or all of it is not up to freeway standards; this includes drawbridges, where traffic on the Interstate can be stopped by boats
- Connection gaps, where a three-digit Interstate does not connect to its two-digit parent via a freeway-standard connection Not covered here are a few other cases worth mentioning:
- Gaps in Interstate Highway standards, such as shoulder widths and bridge clearances, since these are too frequent
- Two-digit Interstate numbers which are meant to be repeated, one on each side of the country, namely I-76, I-84, I-86 and I-88
- Gaps on the Interstates in Alaska and Puerto Rico, since those are not held to the same standards
- Places where Interstates cross but don't connect via a freeway-standard connection (e.g. I-84 and I-87).
- Places where a three-digit Interstate connects to its parent via another three-digit Interstate of the same parent; the numbering system allows for this
- Sometimes, near toll booths (e.g. Mackinac Bridge toll booth), a brief segment of the Interstate will have a median break with a double-yellow line but have at least 4 lanes total (i.e. Super-4).
- Median breaks for maintenance and/or emergency vehicles to access government driveways. These exist on many highways that are otherwise considered freeways, including Interstates.

True gaps

- I-39 had a gap between Rockford, Illinois and Portage, Wisconsin until the late 1990s, when signage was added along I-90 to fill the gap.
- I-74 currently has three sections, one heading west from Cincinnati, Ohio, one from the Virginia/North Carolina state line along I-77 south along I-77 and east to a point southeast of Mount Airy, North Carolina, and one concurrent with the only section of I-73, from Emery, North Carolina to Ulah, North Carolina. Other sections up to freeway standards are signed with I-74 shields that have FUTURE instead of INTERSTATE. Future I-73 shields are also placed along some of these sections, but only one section of I-73 is signed with normal Interstate shields.
- I-90. Many believe that there is presently a gap in I-90 at the Chicago Skyway, but there is controversy and confusion surrounding this issue. Historically the skyway was commonly considered to be, and was signed as, part of I-90. However, around 1999 the City of Chicago, Illinois determined it may never have applied for approval to sign it as an Interstate. (It also is not designed to Interstate standards.) The city resigned the skyway, and it is now mostly posted with "TO I-90" signs, with a few older signs remaining. Because of this development, it has been widely circulated, especially among road buffs, that there is now a gap in I-90. However, the Illinois Department of Transportation has always and continues to report the skyway as part of the Interstate system, and the Federal Highway Administration still considers it as such. A FHWA legal memo says "There is no doubt about it. The Chicago Skyway is officially part of I-90 that (has) always been included in the Dwight D. Eisenhower National System of Interstate and Defense Highways." [http://www.fhwa.dot.gov/programadmin/toll_Rds.html][http://www.tollroadsnews.com/cgi-bin/a.cgi/XeXDlOhBEdmcEIJ61nsxIA]
- I-93 historically has had a gap through Franconia Notch State Park in northern New Hampshire. The road filling the gap, a section of US 3, is built to freeway standards but has only one lane in each direction to avoid adversely impacting the Old Man of the Mountain; such a road is known as a Super-2. Around 2002, the road, which had been signed as US 3 TO I-93, was resigned as a concurrency of I-93 and US 3. Exit numbers, which had been discontinuous with I-93, were renumbered to fit the rest of I-93. Thus this gap may be no more.
- I-95. Probably the most well known and significant of the Interstate gaps, I-95 is discontinuous near Trenton, New Jersey. Coming north from Philadelphia, Pennsylvania, I-95 loops around the north side of Trenton and ends at US 1, where it becomes I-295, which heads back south. The other section of I-95 begins on the Pennsylvania Turnpike at the Pennsylvania/New Jersey state line, and heads north along the New Jersey Turnpike. Originally I-95 was planned have left the alignment north of Trenton and headed northeast to I-287 and run east along I-287 to the Turnpike, but this "Somerset Freeway" was never built. Extensions over the years have taken I-95 several miles further north to the US 1 interchange northeast of Trenton, and south along the New Jersey Turnpike to the Pennsylvania state line. Eventually an interchange will be built connecting the southern alignment with the Pennsylvania Turnpike, and I-95 will be rerouted via it, with the part north of that interchange becoming an extension of I-295.
- I-265 The Indiana portion of I-265 does not yet connect with the Kentucky portion of I-265 at either intended crossing of the Ohio River to form a future beltway around metropolitann Louisville, Kentucky. Funding to complete these two bridges and adjoining freeway has not yet been allocated.

Freeway gaps

- Several Interstates in the southwest U.S. have at-grade intersections (including median breaks) with minor farm access roads. This is usually due to the lack of an old highway, and the need to provide access to property that was accessed via the road before it was upgraded to an Interstate.
- I-40 in the western Texas Panhandle has several driveways coming directly onto the interstate.
- I-70 uses part of US 30 along a surface road in Breezewood, Pennsylvania to get between the freeway heading south to Hancock, Maryland and the ramp to the Pennsylvania Turnpike. Local businesses have lobbied to keep the gap to avoid loss of business.
- I-78 travels along a one-way pair of surface streets, 12th Street and 14th Street, in Jersey City, New Jersey, between the end of the New Jersey Turnpike Newark Bay Extension and the Holland Tunnel.
- I-180 in Cheyenne, Wyoming has no parts built to freeway standards; in fact the interchange with I-80 is even a simple diamond interchange with two traffic lights on I-180, however it is expressway-quality with a few grade-separations.
- I-676 has a surface street section at the west end of the Ben Franklin Bridge in Philadelphia, Pennsylvania because of historically significant areas. Signage and the Federal Highway Administration consider I-676 to use the surface streets, but the Pennsylvania Department of Transportation may consider I-676 to stay on the freeway to end at I-95, with the surface streets and the bridge being only US 30, and the part in New Jersey being a different I-676.
- Interstate 690 in Syracuse, New York has a traffic light for one or two weeks each year, for buses to carry Great New York State Fair attendees from parking areas across the road to the fair.

Undivided freeways

This section talks about Super-2s and other undivided freeway sections of the Interstate.
- I-93 is undivided through Franconia Notch State Park in northern New Hampshire. Used to be a true gap and is now a substandard portion of Interstate freeway.
- The Thousand Islands bridge of Interstate 81 has been undivided.

Drawbridges

- I-5 crosses the Columbia River from Portland, Oregon to Vancouver, Washington on the Interstate Bridge, a drawbridge.
- I-64/Hampton Roads Beltway crosses the South Branch of the Elizabeth River in Chesapeake, Virginia on the High Rise Bridge, a drawbridge.
- I-75 used to cross the Saginaw River in Saginaw, Michigan on the Zilwaukee Bridge, a drawbridge, but a new higher bridge was built.
- I-95 had a drawbridge over the St. Johns River in Jacksonville, Florida (Fuller Warren Bridge) until a new bridge was finished in 2002.
- I-95/I-495/Capital Beltway passes over the Potomac River on the Woodrow Wilson Bridge, a drawbridge, south of Washington, DC. A new higher bridge is being built, but it will still open for tall ships.
- I-95 had a drawbridge across the Hutchinson River in New York, New York until 1996.
- I-110 has a drawbridge across the Back Bay of Biloxi in Biloxi, Mississippi.
- I-264 has a drawbridge over the Elizabeth River in Norfolk, Virginia.
- I-278 has a drawbridge across the Bronx River in New York, New York.
- I-280 has a drawbridge (Stickel Memorial Bridge) over the Passaic River connecting Newark, New Jersey to Harrison, New Jersey.
- I-280 has a drawbridge (Craig Memorial Bridge) over the Maumee River in Toledo, Ohio; a non-drawbridge replacement will be finished in 2006.
- I-395 passes over the Potomac River on the 14th Street Bridge in Washington, DC, which used to be a drawbridge but is now inoperative (adjacent fixed spans constructed in the years leading up to the draw span's decommissioning have a clearance of 18 feet, so permanently shutting the draw span was no particular loss).
- I-695/Baltimore Beltway has a drawbridge over Curtis Creek south of Baltimore, Maryland, a bit to the west of the Francis Scott Key Bridge.

Connection gaps

- I-176 didn't connect directly to I-76 at Morgantown, Pennsylvania until 1996.
- I-238 in San Francisco, in spite of being a three-digit Interstate, does not correspond to an I-38, per normal numbering rules. Indeed, I-38 does not exist, and I-238 actually intersects two spurs of I-80. I-238 was named after CA-238, because there were eight I-80 spurs in California already, and a CA-180. (California does not like to use the same number twice.)
- I-585 used to connect with I-85 in Spartanburg, South Carolina, but I-85 was moved to a bypass and now I-585 ends at Business Loop I-85. The signed connection to I-85 is via a surface section of US 176. Additionally, some I-585 shields are present at the other end after the road has passed traffic lights, but these may be posted in error, since some signs mark the road there as Business Spur I-585.
- I-587 in Kingston, New York connects with I-87 via a roundabout. There are no traffic lights or other cross traffic in the connection, and so it is debated whether this actually counts as a gap.
- The following Interstates connect to their parents only via Interstates of a different parent; it is allowed for this connection to be via a same-parented Interstate (like I-280 in California being connected to I-80 via I-680).
- I-210 in California at present does not directly connect to I-10, though it used to (via what is now CA 57) and will again by 2008 when the last segment of CA 210 is finished and renamed to I-210.
- None of the spurs of I-78 (I-278, I-478, I-678, I-878) connects to its parent. I-78 was planned to extend through New York City and end as two branches, where I-295 and I-695 now end at I-95. I-478 comes the closest, and would have intersected if the Westway project wasn't canceled; I-278 was planned to extend northwest to I-78 at NJ 24.

Sources

- [http://www.roadfan.com/mtrfaq.html misc.transport.road FAQ] Gaps Interstate Highways - gaps

Freeway

.]] A freeway (also superhighway, expressway or motorway as further explained below) is a multi-lane highway (road) designed for high-speed travel by large numbers of vehicles, and having no traffic lights, stop signs, nor other regulations requiring vehicles to stop for cross-traffic.

In general

Design features

Freeways have high speed limits and multiple lanes for travel in each direction. The number of lanes may vary from four or six in rural areas to as high as sixteen or eighteen in certain global cities. A median (originally "medial strip") or central reservation separates the lanes travelling in opposite directions. Separation may be achieved through distance or through the use of high crash barriers like cable barriers and Jersey barriers. Crossroads are bypassed by grade (height) separation using underpasses and overpasses. In addition to the sidewalks attached to roads that go over or under a freeway, most countries also provide specialized pedestrian bridges and underground tunnels. Such structures enable pedestrians and cyclists to cross the freeway without having to make a long detour to the nearest road for which a grade separation has been provided. Freeway entrances and exits are limited in number, and are designed with special onramps and offramps, so as to ensure that vehicles do not disrupt the main flow of traffic as they enter or leave the freeway. In some countries, the exits are numbered. Exit numbering may be by mile or kilometre, or in a simple sequential fashion. Where freeways cross, engineers provide interchanges with elaborate ramp systems that allow for smooth, uninterrupted transitions between all through routes (as funds permit). Because the high speeds reduce decision time, freeways usually have more traffic signs than the equivalent signs on most highways and roads; the signs are often also larger. In major cities, especially on freeways six lanes in width or wider, guide signs are mounted on overpasses or overhead gantries so that drivers can see where each lane goes. Some countries prefer to use a special icon for freeways, while others simply post "Freeway Entrance" and "Begin Freeway" signs. Another common problem with freeways is that it is nearly impossible to avoid wrong-way drivers, and the subsequent head-on collisions are often fatal. Therefore, special signage and lane markings are used to discourage drivers from going the wrong way. Freeways do not usually have traffic lights, but expressways may, in places where this distinction is made.

Gallery of design features

Signage for entering the freeway

Image:Beginfreewaysign.jpg|American "begin freeway" sign Image:Freewayentrancesign.jpg|American on-ramp sign Image:Autorouteentrancesign.jpg|European on-ramp and "begin freeway" sign

Signage for leaving the freeway

Image:Endfreewaysign.jpg|American "End Freeway" warning sign Image:SR 429 north exit 33.jpg|American numbered exit off-ramp sign Image:Autorouteexitsign.jpg|French end of freeway/off-ramp sign

Signage for finding one's way

Image:Americanguidesignage.jpg|American guide signs Image:Americanexitguidesign.jpg|American numbered exit guide sign Image:Quebec exit number.jpg|Canadian guide signs Image:PRC Expressway.jpg|Chinese guide signs Image:SILKhighway.jpg|Malaysian guide signs Image:Europeanguidesignage.jpg|Swiss guide signs Image:AutopistaVespucioSurantesdeRuta5.JPG|Chilean guide signs Image:On the Dhahran-Al Khobar Highway.jpg|Saudi Arabian guide signs

Grade separations

Image:Sandhillroadoverpass.jpg|American freeway overpass

Measures to prevent wrong way drivers

Image:Californiaofframpwrongwaysignage.jpg|Used by some U.S. states at freeway ends and off-ramps

Access restrictions

To minimize accidents, access to freeways is usually limited to vehicles capable of consistently maintaining a high speed, like automobiles, trucks, motorcycles, vans, and buses. Pedestrians, bicyclists, slow-moving vehicles, horses, horse-drawn vehicles, and anything else that might obstruct fast-moving vehicles are all prohibited; however some freeways allow non-motor vehicles (e.g., bicycles) (see non-motorized vehicle access on freeways for more info).

Ancillary facilities

In most parts of the world, there are public rest areas on freeways and expressways as well as other types of highways. In some U.S. states, public rest areas are located almost exclusively on freeways or expressways (since only those routes carry the high traffic necessary to justify the area's maintenance cost).

Nomenclature

Worldwide

Freeway is the term used in most of the United States, parts of Canada, and parts of Australia, notably Victoria, South Australia and Western Australia; the United Kingdom, Republic of Ireland, the rest of Australia and other Commonwealth countries prefer motorway, most of Canada uses expressway, while the province of Québec uses Autoroute; Autoroute is also used in France and other francophone countries; Mexico and other Spanish-speaking countries use the term Autopista; the German-speaking world uses Autobahn, the Dutch-speaking world uses autosnelweg, Italy, Poland and Romania use autostrada; and China and Japan use the term expressway, although they once used freeway. Croatia uses Autocesta, Slovakia uses diaľnica and Czech republic uses dálnice. Some RIRO expressways may have at-grade intersections. Some commentators consider them to be freeways because they have design speeds of 65 mph or higher. However, others argue that RIRO expressways lack complete-controlled access since existing private businesses are allowed to retain their entrances and thus should not be classified as full/true freeways.

United States

The United States definition, as accepted by civil engineers, is that an expressway is any highway to which adjoining property owners do not have a legal right of access. A freeway is an expressway which is free-flowing; that is to say, there are no traffic conflicts on the main line of the highway which must be mediated by a traffic signal, stop signs, or related traffic controls. Another way to look at it is that an expressway is limited-access, and a freeway is controlled-access, but this distinction is not universally accepted. Many non-engineers misapprehend the "free" in "freeway" to mean that such a highway must be free of charge to use. In some states, like California, the vast majority of freeways are toll-free (except where they cross an occasional toll bridge), while other states like Illinois and Florida have toll plazas at every exit on certain expressways. In the U.S., the terms expressway and freeway are legally defined by federal regulation and the laws of most states in accordance with the civil engineering usage just described. However, the distinction between these two terms is not universal, and in several states which built freeways very early on (including Connecticut, Illinois, Massachusetts, New Jersey, New York, Pennsylvania, and Rhode Island), the terms expressway and freeway have the same meaning, and usually expressway or just highway, an older usage, is preferred. In New Jersey and Pennsylvania, newer roads are often officially styled freeways, where older roads retain the title expressway. These are also states which have toll roads, and therefore the distinction is made between a tollway (or turnpike) and a freeway, the latter not costing toll. According to people from these states, an "expressway" is the general category, and then, depending on whether the expressway is toll or free, it may be either a tollway or a freeway. Frequently, in the Midwest and the South, neither "freeway" nor "expressway" is commonly used, and the preferred term is "interstate," even in cases where the expressway might not have been designated an Interstate Highway. In the rest of the country, freeway is the usual term; however, the distinction between freeways and expressways is not always as clear or well-understood as it is in California, which has many of both kinds of highway. Florida has different definitions for both "expressway" and "freeway" than other states. In Florida, an "expressway" is defined as a limited-access toll road, while a "freeway" is any other limited- or controlled-access road which costs no money to travel on.

Canada

In Ontario, while the definitions of "freeway" and "expressway" are consistent with that of the US, "highway" is used far more often than freeway, especially inside the Greater Toronto Area. While this has caused some confusion because the province applies "highway" (The King's Highway) to principal roads in its network, whether freeway or non-freeway, it is usually resolved simply by using the 400-series number to distinguish the freeway. Nonetheless, outside of the GTA, the 400-series numbering does not entirely solve the problem as there are non 400-series freeways built to similar standards such as the Conestoga Parkway (which includes sections of Highways 7, 8 and 85, including a long 7/8 multiplex). The only freeway officially labelled as such is the Macdonald-Cartier Freeway but it is usually known as Highway 401 or "the 401". In Toronto, Ontario, several roads labelled "expressways" in the municipal network are actually fully controlled-access freeways such as the Gardiner Expressway and Spadina Expressway (later renamed Allen Road). Other provinces use varying rules in their official road designations. Alberta and British Columbia have spent millions of dollars investing to make highways into freeways. In Alberta, the main freeway is the Queen Elizabeth II Highway running between Edmonton and Calgary. The road is a freeway through the city of Calgary. Edmonton, however, has many interchanges in progress. On the Trans-Canada Highway west of Calgary, it is a freeway up until the town of Lake Louise. In British Columbia, the main freeways are BC provincial highways 1, 5, and 99.

Construction issues

Freeways have been constructed both between urban centres and within them, making common the style of sprawling suburban development found near most modern cities. As well as reducing travel times, the ease of driving on them reduces accident rates, though the speeds involved also tend to increase the severity and death rate of the collisions (or crashes) that do still happen.

Frontage roads

crash (seen here near Berkeley, California). The frontage road on the far right typically becomes just as congested as the main freeway.]] Because abutters do not have the right of access that they would have for an ordinary public road, the authority undertaking construction of a freeway is frequently required to provide alternate means of access to those landowners. This is frequently accomplished, in areas lacking a dense surface street network, by construction of two uncontrolled roads parallel to and on either side of the freeway, known as frontage roads. These often are designed with one-way traffic flow, but not always. In Texas, where this pattern is perhaps at its zenith, such roads are frequently constructed in anticipation of a future freeway corridor, as many as ten years in advance, in order to influence development patterns on the adjoining land. Frontage roads are also often constructed in more densely-developed areas as a means to provide convenient direct access to and from the parallel freeway while minimizing the need for interchanges at every major cross street. However, some traffic studies have indicated that this particular type of access and the development that ensues generally causes significant traffic congestion and disrupts flows along major freeways. These studies prompted concern for TxDOT, which formally adopted a major shift in frontage road [http://www.abilenetx.com/comp/www.abilenecompplan.com/abilene_comp/documentframeset3fcd.html?docname=http://www.abilenecompplan.com:80/abilene_comp/docs/FrontageRoad.pdf policy] (2002) by stating that no new frontage roads will be built along any proposed limited-access freeways, thus ending a long-standing pattern of freeway-induced development in Texas. Access issues will continue to be assessed on a local basis, and frontage roads could still be constructed if warranted by traffic studies.

Collector lanes

The successor to frontage/service roads in urban freeways is the collector-express system; the lanes accessing (often closely-spaced) interchange ramps are known as collector/distributor roads. Newer suburban freeways are designed with interchanges spaced far apart such that neither service roads or collector lanes are needed.

History

The concept of limited-access automobile highways dates back to the New York City area Parkway system, which began to be constructed in 1907–1908. Designers elsewhere also researched these ideas, especially in Germany, where the Autobahn became the first national freeway system. The term "freeway" first surfaced in the mid-1930s in proposals for the improvement of the New York City parkway network. However, the first true freeway in the United States is generally considered to be the Pennsylvania Turnpike, which opened on October 1, 1940. The Turnpike was so advanced for its time that tourists even had picnics in the median (that is, after it was already open to traffic) and local entrepreneurs did a brisk business in souvenirs. It was designed so that straightaways could handle maximum speeds of 102 miles per hour, and curves could be taken as fast as 90. Shortly thereafter, on December 30, 1940, California opened its first freeway, the Arroyo Seco Parkway (now called the Pasadena Freeway) which connected Pasadena with Los Angeles. And in 1944, Michigan opened its first freeway, the Davison Freeway, within Detroit. Meanwhile, traffic in Los Angeles continued to deteriorate and local officials began planning the huge freeway network for which the city is now famous. Today, many freeways in the United States belong to the extensive Interstate highway system (most of which was completed between 1960 and 1990). Almost all interstates are freeways, but the earlier United States highway system and the highway systems of U.S. states also have many sections that are limited-access (though these systems are mostly composed of uncontrolled roads). Only a handful of sections of the Interstate system are not freeways, such as I-81 as it crosses the American span of the 2-lane Thousand Islands Bridge.

Controversy

I-81, downtown Houston.]] Freeways have been heavily criticized by environmentalists and preservationists for the noise, pollution, and economic shifts they bring. Additionally, they have also been criticized by the driving public for the inefficiency with which they handle peak hour traffic. Often, rural freeways open up vast areas to economic development, generally raising property values. But mature freeways in urban areas are quite often a source of lowered property values, contributing to the deleterious effects of urban blight. One major problem is that even with overpasses and underpasses, freeways tend to divide neighborhoods — especially impoverished ones where residents are less likely to own a car that could easily take them around the freeway. For these reasons, almost no new urban freeways have been built in the U.S. since 1970. Some have even been demolished and reclaimed as boulevards, notably in San Francisco (Embarcadero Freeway) and Milwaukee (Park East Freeway). Some argue that freeway expansion is self-defeating, in that expansion will just generate more traffic. That is, even if traffic congestion is initially shifted from local streets to a new or widened freeway, people will begin to run errands and commutes to more remote locations which took too long to reach in the past. Over time, the freeway and its environs will become congested again as both the average number and distance of trips increase. This is the debated induced demand hypothesis. Pro-freeway advocates point out that properly designed and maintained freeways are aesthetically pleasing, convenient, and safe, at least in comparison to the uncontrolled roads they replace or supplement. Freeways expand recreation, employment and education opportunities for individuals and open new markets to small businesses. And for many, uncongested freeways are fun to drive. Another common argument is that public transit has often failed to relieve traffic congestion, due to the current trend of increasing private car ownership as family wealth levels increase. Public transit projects are just as costly as building freeways, and may constitute an inefficient use of public funds that could have been used more effectively for acquiring right-of-way and