A highway is a main road intended for travel by the public between important destinations, such as cities and towns. Highway designs vary widely and can range from a two-lane road without margins to a multi-lane, grade separated freeway. In law the word highway is often used as a legal term to denote any public road, ranging from freeways to dirt tracks. An interconnected set of highways can be variously referred to as a "highway system", a "highway network" or a "highway transportation system".
The United States has the largest network of highways, including both the Interstate highways and United States Numbered Highways. At least one of these networks is present in every state and connects most major cities. The Expressway Network of the People's Republic of China, also known as National Trunk Highway System (NTHS) has a total length of about 53,600 km at the end of 2007, which is the world's second longest system of expressways only after that of the United States.
Some highways, like the Pan-American Highway or the European routes, bridge multiple countries. Australia's Highway 1 is the longest national highway in the world at over and runs almost the entire way around the country.
Highways are not always continuous stretches of pavement. For example, some highways are interrupted by bodies of water, and ferry routes may serve as sections of the highway.
In Australia, a highway is a distinct type of road from freeways, expressways 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, expressway or motorway are generally reserved for the most arterial routes, usually with grade-separated intersections and usually significantly straightened and widened to a minimum of four lanes. 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. On the Hume Highway when traveling from Melbourne to Sydney there is only one set of traffic signals, found in Holbrook. Roads may be part-highway and part-freeway until they are fully upgraded. The Cahill expressway is the only "named" expressway in New South Wales, which opened in 1954 the first in New South Wales .
Construction of the motorway, whose total length is 340 km, will provide: rational connecting to neighboring countries and regions; stabilizing and developing effects will be reached; transport conditions and quality of life improvement; economy competitiveness enhancement; new projects launched and national and international private investments enhancement.
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:
Often, Brazilian highways receive names (famous people, etc) their YY/BR-XXX designation (example: SP-280 is also known as Rodovia Castelo Branco).
"Highways" in China, more often than not, refer to China National Highways. The fully controlled-access, multi-lane, central-separation routes are instead called expressways. As of 2005, there were 1.55 million km of highways and 42,000 km of expressways in China; both total lengths are second only to the United States.
Expressways are lumped with first-grade G-prefixed guodaos (国道, or "national highway") or A-prefixed first-grade expressways in major municipal cities. All roads in the NTHS and most A-prefixed roads are expressways.
Some highways are numbered with a leading zero (e.g. G030).
The term Freeway during the 1990s was used on a few expressways (such as the Jingshi Freeway). The term freeway has since been replaced with expressway on all signs in China. The Chinese name for expressways is uniform; in pinyin, it is gaosu gonglu, which literally means "high speed public road".
Signs on the National Highways (G-prefix) are green, while on the lower-grade highways and urban expressways (A-prefix) are blue.
Croatia has 9 highways and 8 expressways. The earliest highway in Croatia was built in 1971.
Costa Rica have more than 5 main highway. The most important is the Pan-American Highway (Route 1 and Route 2), known locally as "Interamericana", that communicate Nicaragua and Panama. San José is on the middle of the Pan-American Highway, and such cities as San Pedro and Curridabat have it as the main street. Other important highway in Costa Rica is the Paseo de la Segunda República, that link Guadalupe with La Uruca, crossing Sabanilla, San Pedro, Zapote, Desamparados, San Sebastian, Alajuelita, Hatillos, Santa Ana and Escazú; without passing the downtown of San José. Now, Costa Rican government is improving this highway by the construction of tunnels or bridges.
Also, there are other smaller motorway sections that will be linked to the national motorway network in the future. See here an animation of Hungarian motorway developments (past, present and future): "Térkép animáció" Motorways usually have 2 traffic lanes and an emergency lane on each direction, divided by a green zone and metallic rail. The speed limit is 130 km/h.
Expressways usually have no dividing lane in the middle, but sometimes have a metallic rail. The number of lanes is one per direction, with sections of 1+2 lanes (for easier overtaking). The speed limit is 110 km/h. Motorways and expressways cannot be used by vehicles that are not able to reach 60 km/h. There is a toll on all motorways, except M0. Trucks and buses have a separate toll system. ()
Main roads usually have one lane per direction, no dividing rail. The speed limit is 90 km/h.
County roads have less traffic then main roads, the speed limit is 90 km/h.
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.
In New Zealand, both motorway and an expressway have at least two-lanes of traffic in either direction separated by a median, with no access to adjacent properties. The distinction depends on the type of traffic allowed to use the route. Non-vehicular traffic and farm-equipment are prohibited from motorways, while pedestrians, cyclists, tractors, and farm animals are legally entited to use expressways such as the Waikato Expressway south of the Bombay Hills and the Tauranga expressway system, although this is rare. New Zealand's main routes are designated state highways as they are funded by the National Government. 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 standards 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.
Pakistan has its own network of highways and motorways. Motorways extending from M1 to M10 will eventually connect whole length of the country from Peshawar to Karachi. The first motorway, the M2 was built in 1997 with the contract being awarded to the Korean firm Daewoo. It linked the federal capital Islamabad with Punjab's provincial capital Lahore. The network was then extended to Sargodha and then to Faisalabad with the M3. M1 highway to the North-West Frontier Province's capital Peshawar had been completed in October 2007. M4, M5, M6 and M7 have been planned and also being built by local and foreign firms. This will connect Faisalababd, Multan, Dera Ghazi Khan, Rotadero (Larkana) to Karachi. N5 links Karachi to other cities. Entry on all Pakistan highways is restricted to fast moving wheelers only. Slow-moving traffic and two wheelers (such as motorcycles and bicycles) are not allowed and construction and agricultural machinery is also restricted. Highway Police personnel use heavy motor bikes and fast moving Range Rovers for patrolling and are quite good at maintaining the traffic system. M9 and M10 are also functional now that connect Karachi to Hayderabad. The LSM (Lahore Sialkot Motorway) which is 103 km is under construction and will be completed by 2010.
Many Philippine expressways are privately owned and maintained. All are located in the largest island, Luzon. They follow the US Interstate Highway Standards and speed limits are strictly enforced. The most modern and the longest expressway, the North Luzon Expressway links the capital, Manila to other provinces in Northern Luzon while the South Luzon Expressway links Manila with provinces on the Southern Luzon.
Presently, all Philippine expressways are under rehabilitation to decrease the occurrence of traffic jams and to improve their quality. They are widened and improved of standards.
There are only seven tollways in Luzon Island, the North Luzon Expressway (connecting Manila to North Luzon), the South Luzon Expressway (connecting Manila to Southern Luzon), the Roman Expressway (in Bataan peninsula), Subic Freeport Expressway (connecting Subic Freeport to Dinalupihan), the Southern Tagalog Access Road (STAR Tollway) (connecting Sto. Tomas to Batangas Port, to decongest the Port of Manila and it will be connected directly to South Luzon Expressway), and the Manila-Cavite Expressway, connecting Metro Manila with the Province of Cavite, Subic-Clark-Tarlac Expressway (connecting the existing Subic Freeport Expressway to Clark Zone and Hacienda Luisita and also extending North Luzon Expressway to Tarlac City but it has 3 km gap between NLEx and SCTEx).
Despite that many highways in Metro Manila, there are still two lane and one way roads like national and provincial roads around the country.
There are plans to extend the existing expressways and to build a new one throughout the Philippines, the Tarlac-La Union Expressway aims to extend North Luzon Expressway to the area near Poro Point but it will be extended initially to Rosario in La Union, Tarlac-Dingalan Expressway aims to convert Dingalan into an International Pacific Port and to decongest the Port of Manila, The Cebu Trans-Axial Expressway aims to benefit Cebu's economy and to decongest the island's coastal road and to protect Cebu's coastal areas from severe exploitation, North East Luzon Expressway aims to connect Metro Manila to Cagayan Valley but it will be built initially to Nueva Ecija. South Luzon Expressway will be extended towards Lucena City.
The expressways of Singapore are all dual carriageways with grade-separated access. They usually have three lanes in each direction, although there are two- or four-lane carriageways in some places. There are nine expressways, with another one, the Marina Coastal Expressway, currently under construction.
Construction on the first expressway, the Pan Island Expressway, started in 1966. The other expressways were completed in stages, with the first phase of the Kallang-Paya Lebar Expressway being the most recently completed, in 2007. Today, there are 92.5 miles (148km) of expressways in Singapore.
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.
Spain's national highway system dates back to the era of King Carlos III. The roads built at this time, radiating from Madrid, form the basis for the carreteras nacionales radiales, numbered clockwise from I to VI, which radiate from Madrid to major ports or border crossings. In the 1960s Spain constructed autopistas (toll highways) and autovias, and nowadays (2005) has 15,000 km of highways.
The term Autobahn (German) / Autoroute (French) / Autostrada (Italian) 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 / Semi-autoroute / Semi-autostrada, translated into English as a motorroad. Those often have a lower speed limit than motorways.
In the United Kingdom, unless a route is classified as a motorway, the term used may be main road, trunk road, 'A' road/'B' road, or, where appropriate, dual carriageway. In the law of England and Wales the term highway covers rights of way open to all traffic (as opposed to a footpath for pedestrians or a bridleway for those users plus equestrians), 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:
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.
In the United States, "highway" is a general term for denoting a public way, including the entire area within the right-of-way, and includes many forms:
Many highways are part of the official National Highway System.
However, the United States Numbered Highways system, which predates Interstate Highways, can vary from 2 lanes (1 lane each direction), shoulderless, paved roads with no access control to roads built to the same standards as Interstate Highways. These roads are usually distinguished by being important, but not always primary, routes that connect populated areas.
"Highway" even includes roads that serve similar purposes to United States numbered highways but which are numbered and maintained by state or local governments.
In some places, "highway" is a synonym for "road" or "street". For example, California Motor Vehicle Code § 360 states: "'Highway' is a way or place of whatever nature, publicly maintained and open to the use of the public for purposes of vehicular travel. Highway includes street."
Today, many of the highways in the United States of America are made of concrete and use outdated freeway interchanges. The government is trying to improve its national roadway system by repaving highways and reconstructing various interchanges. Many cloverleaf interchanges are being converted to parclo interchanges, based on the well-received Canadian Ministry of Transportation (Ontario)'s models or other variations. Busy Diamond interchanges are also being converted to SPUIs (single-point-urban interchange) or parclos to reduce congestion.
Arguably, the most famous United States highway is U.S. Route 66. It is immortalized in the song "(Get Your Kicks On) Route 66." Other famous highways of song include Highway 61 (Bob Dylan, 1965), Carefree Highway in Arizona (Gordon Lightfoot, 1974), Colorado Boulevard in Pasadena, California (Jan & Dean, also Beach Boys, 1964), Ventura Highway in California (America, 1972), and Blues Highway in Mississippi (Fred McDowell, 1959).
By reducing travel times relative to arterial streets, highways have a positive effect upon balance of leisure or productive time through reduced commute and other travel time. However, highways have criticisms, partially due to being an extended linear source of pollution:
To quote the Ontario Ministry of Transportation:
New highways can also cause habitat fragmentation, encourage urban sprawl and allow human intrusion into previously untouched areas, as well as (counterintuitively) increasing congestion, by increasing the number of intersections. They can also reduce the use of public transport, indirectly leading to greater pollution.