A highway is any public or private
road
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
or other public way on land. It is used for major roads, but also includes other public roads and public tracks. In some areas of the United States, it is used as an equivalent term to
controlled-access highway
A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...
, or a translation for ''
autobahn
The (; German plural ) is the federal controlled-access highway system in Germany. The official German term is (abbreviated ''BAB''), which translates as 'federal motorway'. The literal meaning of the word is 'Federal Auto(mobile) Track'. ...
'', ''
autoroute'', etc.
According to
Merriam Webster
Merriam-Webster, Inc. is an American company that publishes reference books and is especially known for its dictionaries. It is the oldest dictionary publisher in the United States.
In 1831, George and Charles Merriam founded the company as G ...
, the use of the term predates the 12th century. According to
Etymonline, "high" is in the sense of "main".
In
North American
North America is a continent in the Northern Hemisphere and almost entirely within the Western Hemisphere. It is bordered to the north by the Arctic Ocean, to the east by the Atlantic Ocean, to the southeast by South America and the Ca ...
and
Australian English
Australian English (AusE, AusEng, AuE, AuEng, en-AU) is the set of varieties of the English language native to Australia. It is the country's common language and ''de facto'' national language; while Australia has no official language, Engli ...
, major roads such as controlled-access highways or
arterial road
An arterial road or arterial thoroughfare is a high-capacity urban road that sits below freeways/motorways on the road hierarchy in terms of traffic flow and speed. The primary function of an arterial road is to deliver traffic from collector ro ...
s are often
state highway
A state highway, state road, or state route (and the equivalent provincial highway, provincial road, or provincial route) is usually a road that is either ''numbered'' or ''maintained'' by a sub-national state or province. A road numbered by a ...
s (Canada:
provincial highway
Numbered highways in Canada are split by province, and a majority are maintained by their province or territory transportation department. All highways in Canada are numbered except for three in the Northwest Territories, one in Alberta, one in O ...
s). Other roads may be designated "
county highway
A county highway (also county road or county route; usually abbreviated CH or CR) is a road in the United States and in the Canadian province of Ontario that is designated and/or maintained by the county highway department. Route numbering can ...
s" in the US and
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
. These classifications refer to the level of government (state, provincial, county) that maintains the roadway.
In
British English
British English (BrE, en-GB, or BE) is, according to Lexico, Oxford Dictionaries, "English language, English as used in Great Britain, as distinct from that used elsewhere". More narrowly, it can refer specifically to the English language in ...
, "highway" is primarily a legal term. Everyday use normally implies roads, while the legal use covers any route or path with a public right of access, including
footpath
A footpath (also pedestrian way, walking trail, nature trail) is a type of thoroughfare that is intended for use only by pedestrians and not other forms of traffic such as motorized vehicles, bicycles and horses. They can be found in a wide ...
s etc.
The term has led to several related derived terms, including
highway system,
highway code
''The Highway Code'' is a set of information, advice, guides and mandatory rules for road users in the United Kingdom. Its objective is to promote road safety. The ''Highway Code'' applies to all road users including pedestrians, horse riders ...
,
highway patrol
A highway patrol, or state patrol is either a police unit created primarily for the purpose of overseeing and enforcing traffic safety compliance on roads and highways, or a detail within an existing local or regional police agency that is prima ...
and
highwayman
A highwayman was a robber who stole from travellers. This type of thief usually travelled and robbed by horse as compared to a footpad who travelled and robbed on foot; mounted highwaymen were widely considered to be socially superior to footp ...
.
Overview
Major highways are often named and numbered by the governments that typically develop and maintain them. Australia's
Highway 1 is the longest national highway in the world at over and runs almost the entire way around the continent. China has the world's largest network of highways followed closely by the United States of America. Some highways, like the
Pan-American Highway
The Pan-American Highway (french: (Auto)route panaméricaine/transaméricaine; pt, Rodovia/Auto-estrada Pan-americana; es, Autopista/Carretera/Ruta Panamericana) is a network of roads stretching across the Americas and measuring about in to ...
or the
European route
The international E-road network is a numbering system for roads in Europe developed by the United Nations Economic Commission for Europe, United Nations Economic Commission for Europe (UNECE). The network is numbered from E1 up and its roads ...
s, span multiple countries. Some major highway routes include
ferry
A ferry is a ship, watercraft or amphibious vehicle used to carry passengers, and sometimes vehicles and cargo, across a body of water. A passenger ferry with many stops, such as in Venice, Italy, is sometimes called a water bus or water taxi ...
services, such as
US Route 10, which crosses
Lake Michigan
Lake Michigan is one of the five Great Lakes of North America. It is the second-largest of the Great Lakes by volume () and the third-largest by surface area (), after Lake Superior and Lake Huron. To the east, its basin is conjoined with that o ...
.
Traditionally highways were used by
people on foot or on
horse
The horse (''Equus ferus caballus'') is a domesticated, one-toed, hoofed mammal. It belongs to the taxonomic family Equidae and is one of two extant subspecies of ''Equus ferus''. The horse has evolved over the past 45 to 55 million y ...
s. Later they also accommodated
carriage
A carriage is a private four-wheeled vehicle for people and is most commonly horse-drawn. Second-hand private carriages were common public transport, the equivalent of modern cars used as taxis. Carriage suspensions are by leather strapping an ...
s,
bicycles
A bicycle, also called a pedal cycle, bike or cycle, is a human-powered or motor-powered assisted, pedal-driven, single-track vehicle, having two wheels attached to a frame, one behind the other. A is called a cyclist, or bicyclist.
Bic ...
and eventually
motor car
A car or automobile is a motor vehicle with wheels. Most definitions of ''cars'' say that they run primarily on roads, seat one to eight people, have four wheels, and mainly transport people instead of goods.
The year 1886 is regarded as t ...
s, facilitated by advancements in
road construction
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
. In the 1920s and 1930s, many nations began investing heavily in progressively more modern highway systems to spur
commerce
Commerce is the large-scale organized system of activities, functions, procedures and institutions directly and indirectly related to the exchange (buying and selling) of goods and services among two or more parties within local, regional, nation ...
and bolster national defence.
Major modern highways that connect cities in populous
developed and
developing countries
A developing country is a sovereign state with a lesser developed industrial base and a lower Human Development Index (HDI) relative to other countries. However, this definition is not universally agreed upon. There is also no clear agreem ...
usually incorporate features intended to enhance the road's capacity, efficiency, and safety to various degrees. Such features include a
reduction in the number of locations for user access, the use of
dual carriageway
A dual carriageway ( BE) or divided highway ( AE) is a class of highway with carriageways for traffic travelling in opposite directions separated by a central reservation (BrE) or median (AmE). Roads with two or more carriageways which are ...
s with two or more lanes on each carriageway, and
grade-separated
In civil engineering (more specifically highway engineering), grade separation is a method of aligning a junction of two or more surface transport axes at different heights (grades) so that they will not disrupt the traffic flow on other tran ...
junctions with other roads and modes of transport. These features are typically present on highways built as ''
motorway
A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...
s'' (''
freeway
A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms ...
s'').
Terminology
England and Wales
The general legal definition deals with right of use not the form of construction; this is distinct from e.g. the popular use of the word in the US. A highway is defined in English
common law
In law, common law (also known as judicial precedent, judge-made law, or case law) is the body of law created by judges and similar quasi-judicial tribunals by virtue of being stated in written opinions."The common law is not a brooding omnipresen ...
by a number of similarly-worded definitions such as "a way over which all members of the public have the right to pass and repass without hindrance" usually accompanied by "at all times"; ownership of the ground is for most purposes irrelevant, thus the term encompasses all such ways from the widest trunk roads in public ownership to the narrowest footpath providing unlimited pedestrian access over private land.
A highway might be open to all forms of lawful land traffic (e.g. vehicular, horse, pedestrian) or limited to specific types of traffic or combinations of types of traffic; usually a highway available to vehicles is available to foot or horse traffic, a highway available to horse traffic is available to pedestrians but exceptions can apply usually in the form of a highway only being available to vehicles or subdivided into dedicated parallel sections for different users.
A highway can share ground with a private right of way for which full use is not available to the general public as often will be the case with farm roads which the owner may use for any purpose but for which the general public only has a right of use on foot or horseback. The status of ''highway'' on most older roads has been gained by established public use while newer roads are typically ''dedicated'' as highways from the time they are adopted (taken into the care and control of a council or other public authority). In England and Wales, a public highway is also known as "''The Queen's Highway''".
The core definition of a highway is modified in various legislation for a number of purposes but only for the specific matters dealt with in each such piece of legislation. This is typically in the case of bridges, tunnels and other structures whose ownership, mode of use or availability would otherwise exclude them from the general definition of a highway, examples in recent years are commonly toll bridges and tunnels which have the definition of ''highway'' imposed upon them (in a legal order applying only to the individual structure) to allow application of most traffic laws to those using them but without causing all of the general obligations or rights of use otherwise applicable to a highway.
What is called 'highway' in the context of motor vehicles is called 'motorway' in the UK context.
Scotland
Scots law
Scots law () is the legal system of Scotland. It is a hybrid or mixed legal system containing civil law and common law elements, that traces its roots to a number of different historical sources. Together with English law and Northern Ireland l ...
is similar to English law with regard to highways but with differing terminology and legislation. What is defined in England as a ''highway'' will often in Scotland be what is defined by s.151
Roads (Scotland) Act 1984
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
(but only "in this act" although other legislation could imitate) simply as a road, that is :-
*"any way (other than a waterway) over which there is a public right of passage (by whatever means
nd whether subject to a toll or not and includes the road’s verge, and any bridge (whether permanent or temporary) over which, or tunnel through which, the road passes; and any reference to a road includes a part thereof; "
The word ''highway'' is itself no longer a statutory expression in Scots law but remains in common law.
United States
In American law, the word "highway" is sometimes used to denote any public way used for travel, whether a "road, street, and parkway";
however, in practical and useful meaning, a "highway" is a major and significant, well-constructed road that is capable of carrying reasonably heavy to extremely heavy traffic. Highways generally have a route number designated by the state and federal departments of transportation.
California Vehicle Code, Sections 360, 590, define a "highway" as only a way open for use of motor vehicles, but the California Supreme Court has held that "the definition of 'highway' in the Vehicle Code is used for special purposes of that act," and that canals of the Los Angeles neighborhood of
Venice, California
Venice is a neighborhood of the city of Los Angeles within the Westside region of Los Angeles County, California.
Venice was founded by Abbot Kinney in 1905 as a seaside resort town. It was an independent city until 1926, when it was annexed b ...
, are "highways" that are entitled to be maintained with state highway funds.
History
Modern highway systems developed in the 20th century as the
automobile
A car or automobile is a motor vehicle with Wheel, wheels. Most definitions of ''cars'' say that they run primarily on roads, Car seat, seat one to eight people, have four wheels, and mainly transport private transport#Personal transport, pe ...
gained popularity. The first United States
limited access road
A limited-access road, known by various terms worldwide, including limited-access highway, dual-carriageway, expressway, limited access freeway, and partial controlled access highway, is a highway or arterial road for high-speed traffic which ...
was constructed on Long Island New York known as the
Long Island Motor Parkway
The Long Island Motor Parkway, also known as the Vanderbilt Parkway, Vanderbilt Motor Parkway, or Motor Parkway, was a roadway on Long Island, New York, in the United States. It was the first roadway designed for automobile use only. The parkway ...
or the Vanderbilt Motor Parkway. It was completed in 1911.
In Italy the Milano-Varese autostrada was opened in 1924.
Construction of the Bonn–Cologne
autobahn
The (; German plural ) is the federal controlled-access highway system in Germany. The official German term is (abbreviated ''BAB''), which translates as 'federal motorway'. The literal meaning of the word is 'Federal Auto(mobile) Track'. ...
began in 1929 and it was opened in 1932 by the mayor of
Cologne
Cologne ( ; german: Köln ; ksh, Kölle ) is the largest city of the German western States of Germany, state of North Rhine-Westphalia (NRW) and the List of cities in Germany by population, fourth-most populous city of Germany with 1.1 m ...
,
Konrad Adenauer
Konrad Hermann Joseph Adenauer (; 5 January 1876 – 19 April 1967) was a Germany, German statesman who served as the first Chancellor of Germany, chancellor of the Federal Republic of Germany from 1949 to 1963. From 1946 to 1966, he was the fir ...
.
In the US, the
Federal Aid Highway Act of 1921 (Phipps Act)
Federal or foederal (archaic) may refer to:
Politics
General
*Federal monarchy, a federation of monarchies
*Federation, or ''Federal state'' (federal system), a type of government characterized by both a central (federal) government and states or ...
enacted a fund to create an extensive highway system. In 1922, the first blueprint for a national highway system (the
Pershing Map
The Pershing Map was the first blueprint for a national highway system in the United States, with many of the proposed roads later forming a substantial portion of the Interstate Highway System.
History
When the United States Army realized it cou ...
) was published. The
Federal Aid Highway Act of 1956
The Federal-Aid Highway Act of 1956, also known as the National Interstate and Defense Highways Act, was enacted on June 29, 1956, when President Dwight D. Eisenhower signed the bill into law. With an original authorization of $25 billion for t ...
allocated $25 billion for the construction of the
Interstate Highway System
The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. Th ...
over a 20-year period.
In
Great Britain
Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It is ...
, the
Special Roads Act 1949
The Special Roads Act 1949 (c.32) was an Act of the Parliament of the United Kingdom that:
*Authorised the construction of special roads (that became known as motorways)
*Allowed these roads to be restricted to specific types of vehicles
The S ...
provided the legislative basis for roads for restricted classes of vehicles and non-standard or no speed limits applied (later mostly termed
motorway
A controlled-access highway is a type of highway that has been designed for high-speed vehicular traffic, with all traffic flow—ingress and egress—regulated. Common English terms are freeway, motorway and expressway. Other similar terms i ...
s but now with speed limits not exceeding 70 mph); in terms of general road law this legislation overturned the usual principle that a road available to vehicular traffic was also available to horse or pedestrian traffic as is usually the only practical change when non-motorways are reclassified as ''special roads''. The first section of motorway in the UK opened in 1958 (part of the M6 motorway) and then in 1959 the first section of the
M1 motorway
The M1 motorway connects London to Leeds, where it joins the A1(M) near Aberford, to connect to Newcastle. It was the first inter-urban motorway to be completed in the UK; the first motorway in the country was the Preston By-pass, which lat ...
.
Social effects
Reducing travel times relative to city or town streets, modern highways with limited access and grade separation create increased opportunities for people to travel for business, trade or pleasure and also provide trade routes for goods. Modern highways reduce commute and other travel time but additional road capacity can also release
latent traffic demand. If not accurately predicted at the planning stage, this extra traffic may lead to the new road becoming congested sooner than would otherwise be anticipated by considering increases in vehicle ownership. More roads allow drivers to use their cars when otherwise alternatives may have been sought, or the journey may not have been made, which can mean that a new road brings only short-term mitigation of traffic congestion.
Where highways are created through existing communities, there can be reduced
community cohesion
Community cohesion is a conceptual framework which attempts to measure the social relationships within a community. It relies on criteria such as: the presence of a shared vision, inclusion of those with diverse backgrounds, equal opportunity, and ...
and more difficult local access. Consequently, property values have decreased in many cutoff neighborhoods, leading to decreased housing quality over time.
Economic effects
In transport,
demand
In economics, demand is the quantity of a good that consumers are willing and able to purchase at various prices during a given time. The relationship between price and quantity demand is also called the demand curve. Demand for a specific item ...
can be measured in numbers of journeys made or in total distance travelled across all journeys (e.g.
passenger-kilometre
The units of measurement in transportation describes the unit of measurement used to express various transportation quantities, as used in statistics, planning, and their related applications.
Transportation quantity
The currently popular units ...
s for
public transport
Public transport (also known as public transportation, public transit, mass transit, or simply transit) is a system of transport for passengers by group travel systems available for use by the general public unlike private transport, typical ...
or vehicle-kilometres of travel (VKT) for
private transport
Private transport (as opposed to public transport) is the personal or individual use of transportation which are not available for use by the general public, where in theory the user can decide freely on the time and route of transit ('choice ...
).
Supply
Supply may refer to:
*The amount of a resource that is available
**Supply (economics), the amount of a product which is available to customers
**Materiel, the goods and equipment for a military unit to fulfill its mission
*Supply, as in confidenc ...
is considered to be a measure of capacity. The
price
A price is the (usually not negative) quantity of payment or compensation given by one party to another in return for goods or services. In some situations, the price of production has a different name. If the product is a "good" in the c ...
of the good (travel) is measured using the
generalised cost
In transport economics, the generalised cost is the sum of the monetary and non-monetary costs of a journey. It is sometimes used as a basis for judgements of transit accessibility and equitable distribution of public transit resources.
Monetary ...
of travel, which includes both
money
Money is any item or verifiable record that is generally accepted as payment for goods and services and repayment of debts, such as taxes, in a particular country or socio-economic context. The primary functions which distinguish money are as ...
and
time
Time is the continued sequence of existence and events that occurs in an apparently irreversible succession from the past, through the present, into the future. It is a component quantity of various measurements used to sequence events, to ...
expenditure.
The effect of increases in supply (capacity) are of particular interest in transport economics (see
induced demand
In economics, induced demand – related to latent demand and generated demandSchneider, Benjamin (September 6, 2018"CityLab University: Induced Demand"''CityLab'' – is the phenomenon whereby an increase in supply results in a decline ...
), as the potential environmental consequences are significant (see ''externalities'' below).
In addition to providing benefits to their users, transport networks impose both
positive
Positive is a property of positivity and may refer to:
Mathematics and science
* Positive formula, a logical formula not containing negation
* Positive number, a number that is greater than 0
* Plus sign, the sign "+" used to indicate a posit ...
and
negative externalities
In economics, an externality or external cost is an indirect cost or benefit to an uninvolved third party that arises as an effect of another party's (or parties') activity. Externalities can be considered as unpriced goods involved in either co ...
on non-users. The consideration of these externalities—particularly the negative ones—is a part of transport economics. Positive externalities of transport networks may include the ability to provide
emergency services
Emergency services and rescue services are organizations that ensure public safety and health by addressing and resolving different emergencies. Some of these agencies exist solely for addressing certain types of emergencies, while others deal wit ...
, increases in
land
Land, also known as dry land, ground, or earth, is the solid terrestrial surface of the planet Earth that is not submerged by the ocean or other bodies of water. It makes up 29% of Earth's surface and includes the continents and various islan ...
value and
agglomeration benefits. Negative externalities are wide-ranging and may include local
air pollution
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...
,
noise pollution
Noise pollution, also known as environmental noise or sound pollution, is the propagation of noise with ranging impacts on the activity of human or animal life, most of them are harmful to a degree. The source of outdoor noise worldwide is main ...
,
light pollution
Light pollution is the presence of unwanted, inappropriate, or excessive use of artificial Visible spectrum, lighting. In a descriptive sense, the term ''light pollution'' refers to the effects of any poorly implemented lighting, during the day ...
,
safety hazards,
community severance
A community is a social unit (a group of living things) with commonality such as place, norms, religion, values, customs, or identity. Communities may share a sense of place situated in a given geographical area (e.g. a country, village, tow ...
and
congestion. The contribution of transport systems to potentially hazardous
climate change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to E ...
is a significant negative externality which is difficult to evaluate quantitatively, making it difficult (but not impossible) to include in transport economics-based research and analysis. Congestion is considered a negative
externality
In economics, an externality or external cost is an indirect cost or benefit to an uninvolved third party that arises as an effect of another party's (or parties') activity. Externalities can be considered as unpriced goods involved in either co ...
by economists.
A 2016 study finds that for the United States "a 10% increase in a region's stock of highways causes a 1.7% increase in regional patenting over a five-year period." A 2021 study found that areas that obtained access to a new highway experienced a substantial increase in top-income taxpayers and a decline in low-income taxpayers. Highways also contributed to job and residential urban sprawl.
Environmental effects
Highways are extended
linear sources of
pollution
Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...
.
Roadway noise
Roadway noise is the collective sound energy emanating from motor vehicles. It consists chiefly of road surface, tire, engine/transmission, aerodynamic, and braking elements. Noise of rolling tires driving on pavement is found to be the biggest ...
increases with operating speed so major highways generate more noise than
arterial
An artery (plural arteries) () is a blood vessel in humans and most animals that takes blood away from the heart to one or more parts of the body (tissues, lungs, brain etc.). Most arteries carry oxygenated blood; the two exceptions are the pul ...
streets. Therefore, considerable
noise health effects
Noise health effects are the physical and psychological health consequences of regular exposure to consistent elevated sound levels. Noise from traffic, in particular, is considered by the World Health Organization to be one of the worst environm ...
are expected from highway systems.
Noise mitigation
Noise control or noise mitigation is a set of strategies to reduce noise pollution or to reduce the impact of that noise, whether outdoors or indoors.
Overview
The main areas of noise mitigation or abatement are: transportation noise control, ...
strategies exist to reduce sound levels at nearby
sensitive receptors. The idea that highway design could be influenced by
acoustical engineering
Acoustical engineering (also known as acoustic engineering) is the branch of engineering dealing with sound and vibration. It includes the application of acoustics, the science of sound and vibration, in technology. Acoustical engineers are typical ...
considerations first arose about 1973.
Air quality
Air pollution is the contamination of air due to the presence of substances in the atmosphere that are harmful to the health of humans and other living beings, or cause damage to the climate or to materials. There are many different types ...
issues: Highways may contribute fewer
emissions
Emission may refer to:
Chemical products
* Emission of air pollutants, notably:
**Flue gas, gas exiting to the atmosphere via a flue
** Exhaust gas, flue gas generated by fuel combustion
** Emission of greenhouse gases, which absorb and emit rad ...
than arterials carrying the same vehicle volumes. This is because high, constant-speed operation creates an emissions reduction compared to vehicular flows with stops and starts. However, concentrations of air pollutants near highways may be higher due to increased traffic volumes. Therefore, the risk of exposure to elevated levels of air pollutants from a highway may be considerable, and further magnified when highways have
traffic congestion
Traffic congestion is a condition in transport that is characterized by slower speeds, longer trip times, and increased vehicular queueing. Traffic congestion on urban road networks has increased substantially since the 1950s. When traffic de ...
.
New highways can also cause
habitat fragmentation
Habitat fragmentation describes the emergence of discontinuities (fragmentation) in an organism's preferred environment (habitat), causing population fragmentation and ecosystem decay. Causes of habitat fragmentation include geological processes ...
, encourage
urban sprawl
Urban sprawl (also known as suburban sprawl or urban encroachment) is defined as "the spreading of urban developments (such as houses and shopping centers) on undeveloped land near a city." Urban sprawl has been described as the unrestricted growt ...
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
Public transport (also known as public transportation, public transit, mass transit, or simply transit) is a system of transport for passengers by group travel systems available for use by the general public unlike private transport, typical ...
, indirectly leading to greater pollution.
High-occupancy vehicle lane
A high-occupancy vehicle lane (also known as an HOV lane, carpool lane, diamond lane, 2+ lane, and transit lane or T2 or T3 lanes) is a restricted traffic lane reserved for the exclusive use of vehicles with a driver and one or more passengers, i ...
s are being added to some newer/reconstructed highways in the United States and other countries around the world to encourage
carpooling
Carpooling (also car-sharing, ride-sharing and lift-sharing) is the sharing of car journeys so that more than one person travels in a car, and prevents the need for others to have to drive to a location themselves.
By having more people usi ...
and mass-transit. These lanes help reduce the number of cars on the highway and thus reduces pollution and traffic congestion by promoting the use of carpooling in order to be able to use these lanes. However, they tend to require dedicated lanes on a highway, which makes them difficult to construct in dense urban areas where they are the most effective.
To address habitat fragmentation,
wildlife crossings
Wildlife crossings are structures that allow animals to cross human-made barriers safely. Wildlife crossings may include underpass tunnels or wildlife tunnels, viaducts, and overpasses or green bridges (mainly for large or herd-type animals) ...
have become increasingly popular in many countries. Wildlife crossings allow animals to safely cross human-made barriers like highways.
Road traffic safety
Road traffic safety
Road traffic safety refers to the methods and measures used to prevent road users from being killed or seriously injured. Typical road users include pedestrians, cyclists, motorists, vehicle passengers, horse riders, and passengers of on-road ...
describes the safety performance of roads and streets, and methods used to reduce the harm (deaths, injuries, and property damage) on the highway system from
traffic collisions. It includes the design, construction and regulation of the
roads
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
, the
vehicle
A vehicle (from la, vehiculum) is a machine that transports people or cargo. Vehicles include wagons, bicycles, motor vehicles (motorcycles, cars, trucks, buses, mobility scooters for disabled people), railed vehicles (trains, trams), wa ...
s used on them and the training of drivers and other road-users.
A report published by the
World Health Organization
The World Health Organization (WHO) is a specialized agency of the United Nations responsible for international public health. The WHO Constitution states its main objective as "the attainment by all peoples of the highest possible level of h ...
in 2004 estimated that some 1.2 million people were killed and 50 million injured on the roads around the world each year and was the leading cause of death among children 10–19 years of age.
The report also noted that the problem was most severe in developing countries and that simple prevention measures could halve the number of deaths.
For reasons of clear data collection, only harm involving a road vehicle is included.
A person tripping with fatal consequences or dying for some unrelated reason on a public road is not included in the relevant statistics.
Statistics
The United States has the world's largest network of highways, including both the
Interstate Highway System
The Dwight D. Eisenhower National System of Interstate and Defense Highways, commonly known as the Interstate Highway System, is a network of controlled-access highways that forms part of the National Highway System in the United States. Th ...
and the
United States Numbered Highway System
The United States Numbered Highway System (often called U.S. Routes or U.S. Highways) is an integrated network of roads and highways numbered within a nationwide grid in the contiguous United States. As the designation and numbering of these hi ...
. At least one of these networks is present in every state and they interconnect most major cities.
China's highway network is the second most extensive in the world, with a total length of about .
China's
expressway
Expressway may refer to:
* Controlled-access highway, the highest-grade type of highway with access ramps, lane markings, etc., for high-speed traffic.
* Limited-access road, a lower grade of highway or arterial road.
*Expressway, the fictional s ...
network is the longest Expressway system in the world, and it is quickly expanding, stretching some at the end of 2011. In 2008 alone, expressways were added to the network.
;Longest international highway: The
Pan-American Highway
The Pan-American Highway (french: (Auto)route panaméricaine/transaméricaine; pt, Rodovia/Auto-estrada Pan-americana; es, Autopista/Carretera/Ruta Panamericana) is a network of roads stretching across the Americas and measuring about in to ...
, which connects many countries in the
Americas
The Americas, which are sometimes collectively called America, are a landmass comprising the totality of North and South America. The Americas make up most of the land in Earth's Western Hemisphere and comprise the New World.
Along with th ...
, is nearly long . The Pan-American Highway is discontinuous because there is a
significant gap in it in southeastern
Panama
Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...
, where the rainfall is immense and the terrain is entirely unsuitable for highway construction.
;Longest national highway (point to point): The
Trans-Canada Highway
The Trans-Canada Highway ( French: ; abbreviated as the TCH or T-Can) is a transcontinental federal–provincial highway system that travels through all ten provinces of Canada, from the Pacific Ocean on the west coast to the Atlantic Ocean o ...
has one main route, a northern route through the
western provinces
Western Canada, also referred to as the Western provinces, Canadian West or the Western provinces of Canada, and commonly known within Canada as the West, is a Canadian region that includes the four western provinces just north of the Canada– ...
, and several branches in the
central
Central is an adjective usually referring to being in the center of some place or (mathematical) object.
Central may also refer to:
Directions and generalised locations
* Central Africa, a region in the centre of Africa continent, also known as ...
and
eastern provinces. The main route is long alone, and the entire system is over long. The TCH runs east-west across southern Canada, the populated portion of the country, and it connects many of the major urban centres along its route crossing all provinces, and reaching nearly all of their capital cities.
The TCH begins on the east coast in
Newfoundland
Newfoundland and Labrador (; french: Terre-Neuve-et-Labrador; frequently abbreviated as NL) is the easternmost province of Canada, in the country's Atlantic region. The province comprises the island of Newfoundland and the continental region ...
, traverses that island, and crosses to the mainland by ferry. It crosses the
Maritime Provinces
The Maritimes, also called the Maritime provinces, is a region of Eastern Canada consisting of three provinces: New Brunswick, Nova Scotia, and Prince Edward Island. The Maritimes had a population of 1,899,324 in 2021, which makes up 5.1% of Ca ...
of eastern Canada with a branch route serving the province of
Prince Edward Island
Prince Edward Island (PEI; ) is one of the thirteen Provinces and territories of Canada, provinces and territories of Canada. It is the smallest province in terms of land area and population, but the most densely populated. The island has seve ...
via a ferry and bridge. After crossing the remainder of the country's mainland, the highway reaches
Vancouver
Vancouver ( ) is a major city in western Canada, located in the Lower Mainland region of British Columbia. As the List of cities in British Columbia, most populous city in the province, the 2021 Canadian census recorded 662,248 people in the ...
,
British Columbia
British Columbia (commonly abbreviated as BC) is the westernmost province of Canada, situated between the Pacific Ocean and the Rocky Mountains. It has a diverse geography, with rugged landscapes that include rocky coastlines, sandy beaches, ...
on the
Pacific coast
Pacific coast may be used to reference any coastline that borders the Pacific Ocean.
Geography Americas
Countries on the western side of the Americas have a Pacific coast as their western or southwestern border, except for Panama, where the Pac ...
, where a ferry continues it to
Vancouver Island
Vancouver Island is an island in the northeastern Pacific Ocean and part of the Canadian Provinces and territories of Canada, province of British Columbia. The island is in length, in width at its widest point, and in total area, while are o ...
and the provincial capital of
Victoria
Victoria most commonly refers to:
* Victoria (Australia), a state of the Commonwealth of Australia
* Victoria, British Columbia, provincial capital of British Columbia, Canada
* Victoria (mythology), Roman goddess of Victory
* Victoria, Seychelle ...
. Numeric designation is the responsibility of the provinces, and there is no single route number across the country.
;Longest national highway (circuit): Australia's
Highway 1 at over . It runs almost the entire way around the country's coastline. With the exception of the Federal Capital of
Canberra
Canberra ( )
is the capital city of Australia. Founded following the federation of the colonies of Australia as the seat of government for the new nation, it is Australia's largest inland city and the eighth-largest city overall. The ci ...
, which is far inland, Highway 1 links all of Australia's capital cities, although Brisbane and Darwin are not directly connected, but rather are bypassed short distances away. Also, there is a ferry connection to the island state of
Tasmania
)
, nickname =
, image_map = Tasmania in Australia.svg
, map_caption = Location of Tasmania in AustraliaCoordinates:
, subdivision_type = Country
, subdi ...
, and then a stretch of Highway 1 that links the major towns and cities of Tasmania, including
Launceston and
Hobart
Hobart ( ; Nuennonne/Palawa kani: ''nipaluna'') is the capital and most populous city of the Australian island state of Tasmania. Home to almost half of all Tasmanians, it is the least-populated Australian state capital city, and second-small ...
(this state's capital city).
;Largest national highway system: The United States of America has approximately of highway within its borders .
;Busiest highway:
Highway 401
King's Highway 401, commonly referred to as Highway 401 and also known by its official name as the Macdonald–Cartier Freeway or colloquially referred to as the four-oh-one,
is a controlled-access 400-series highway in the Canadian provin ...
in
Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
, Canada, has volumes surpassing an average of 500,000 vehicles per day in some sections of Toronto .
;Widest highway (maximum number of lanes): The
Katy Freeway
Katy or KATY may refer to:
People
* Katy, a short form of the name Katherine
* Katy (given name)
* Katy (Marvel Cinematic Universe), a fictional character
* Katy Perry
Places Serbia
* Kać, Serbia ( hu, Káty, link=no)
United States
* Katy, Mi ...
(part of
Interstate 10
Interstate 10 (I-10) is the southernmost cross-country highway in the American Interstate Highway System. I-10 is the fourth-longest Interstate in the United States at , following I-90, I-80, and I-40. This freeway is part of the originally pl ...
) in
Houston
Houston (; ) is the most populous city in Texas, the most populous city in the Southern United States, the fourth-most populous city in the United States, and the sixth-most populous city in North America, with a population of 2,304,580 in ...
,
Texas
Texas (, ; Spanish language, Spanish: ''Texas'', ''Tejas'') is a state in the South Central United States, South Central region of the United States. At 268,596 square miles (695,662 km2), and with more than 29.1 million residents in 2 ...
, has a total of 26 lanes in some sections . However, they are divided up into general use/ frontage roads/ HOV lanes, restricting the traverse traffic flow.
;Widest highway (maximum number of through lanes): Interstate 5 in California, Interstate 5 along a section between Interstate 805 and California State Route 56 in San Diego, California, which was completed in April 2007, is 22 lanes wide.
;Highest international highway: The Karakoram Highway, between Pakistan and China, is at an altitude of .;
;Highest national highway: National Highway 5 (India), National Highway 5, in India, connecting Amritsar in Punjab with Manali, Himachal Pradesh, Manali in Himachal Pradesh & Leh in Ladakh, reaches an approximate altitude of .. The highest motorable road passes through Umling La at an altitude of falls under the branch highway connecting National Highway 5 in India.
Bus lane
Some countries incorporate bus lanes onto highways.
South Korea
In South Korea, in February 1995 a bus lane (essentially an HOV-9) was established between the northern terminus and Sintanjin for important holidays and on 1 July 2008 bus lane enforcement between Seoul and Osan (Sintanjin on weekends) became daily between 6 a.m. and 10 p.m. On 1 October this was adjusted to 7 a.m. to 9 p.m. weekdays, and 9 a.m. to 9 p.m. weekends.
Hong Kong
In Hong Kong, some highways are set up with bus lanes to solve the traffic congestion.
Philippines
Traffic congestion was a principal problem in major
roads
A road is a linear way for the conveyance of traffic that mostly has an improved surface for use by vehicles (motorized and non-motorized) and pedestrians. Unlike streets, the main function of roads is transportation.
There are many types of ...
and highways in the Philippines, especially in Metro Manila and other major cities. The government decided to set up some bus lanes in Metro Manila like in the Epifanio delos Santos Avenue.
Gallery
File:Spaghetti-Junction-Crop.jpg, Gravelly Hill Interchange in Birmingham, England
File:Autogrill-greece-A1 2009.jpg, Motorway 1 (Greece), A1 Motorway near Athens, Greece with rest area above
File:A1 (A14 Bologna B.go Panigale).JPG, The ten-lane A1 motorway (Italy), Highway A1 near Bologna, Italy
File:S1 1.JPG, A Roads and expressways in Poland, Polish expressway in Bielsko-Biała
File:5, 70870 Kuopio, Finland - panoramio.jpg, Finnish national road 5, National road 5 in Kuopio, Finland
File:E4 Nyköpingsbro.jpg, European route E4, E4 motorway with rest area outside Nyköping, Sweden
File:401 widest point.jpg, Highway 401
King's Highway 401, commonly referred to as Highway 401 and also known by its official name as the Macdonald–Cartier Freeway or colloquially referred to as the four-oh-one,
is a controlled-access 400-series highway in the Canadian provin ...
with Local-express lanes, collector and express lanes in Mississauga, Ontario
Ontario ( ; ) is one of the thirteen provinces and territories of Canada.Ontario is located in the geographic eastern half of Canada, but it has historically and politically been considered to be part of Central Canada. Located in Central Ca ...
, Canada
File:Garching_Bundesautobahn_9.jpg, Multi-lane Autobahn 9 in Munich, Germany
File:Pan-American Highway-Mancora, Peru.jpg, The Pan-American Highway
The Pan-American Highway (french: (Auto)route panaméricaine/transaméricaine; pt, Rodovia/Auto-estrada Pan-americana; es, Autopista/Carretera/Ruta Panamericana) is a network of roads stretching across the Americas and measuring about in to ...
where it serves as the main street in Máncora, Peru
File:PRC Expressway.jpg, A typical expressway in China
File:S85(Guizhou) Duyun Direction Exit 332 close to G75.jpg, An expressway exit in Guizhou, China
File:Klaukkala-Loppi-kyltti, E12.jpg, The Tampere Highway in Vantaa, Finland
File:North Lantau Highway near Citygate (Hong Kong).jpg, North Lantau Highway in Hong Kong
File: Delhi Noida Direct flyway (Uttar Pradesh - 2011-06-18).jpg, A typical expressway in India
File:Delhi Gurgaon Toll Gate.jpg, 32-lane toll plaza at Delhi-Gurgaon Expressway in Gurgaon, India
File:HIghway Chennai Bangalore.jpg, Chennai-Bangalore Golden Quadrilateral, Highway
File:Express highway.jpg, Mumbai Pune Expressway, India
File:Kordestan-Resalat-Hakim.jpg, A highway interchange in Tehran, Iran
File:Tokyo EXP way.JPG, The Metropolitan Expressway in Tokyo, Japan
File:Kuwait highway.jpg, A highway in Kuwait City
File:2007 08 21 China Pakistan Karakoram Highway Khunjerab Pass IMG 7295.jpg, Karakoram Highway, Pakistan
File:FvfValenzuela1372 37.JPG, North Luzon Expressway, the Philippines
File:Jisu IC in Namhae Expressway.JPG, Namhae Expressway in Jinju, South Korea
File:The-Expressway_at_Ja-ela.jpg, Ja-Ela Interchange in the E03 expressway (Sri Lanka), Airport Expressway(E03) in Ja-Ela, Sri Lanka
File:Dubai Roads on 1 May 2007.jpg, 3/4 highway interchange in Dubai, United Arab Emirates
File:Quoclo1Amoi.JPG, National Route 1 (Vietnam), National Route 1 near Tu Son, Từ Sơn, Vietnam
See also
General
* Bypass route
* Controlled-access highway
* Divided highway, Divided highway (dual carriageway)
* Freeway
* Highway systems by country
* Highwayman
* Infrastructure
* Limited-access road
* List of roads and highways
* Motorway
* Parkway
* Passing lane
* Ring road
* Road
* Road junction
* Road safety
* Road transport
* Roadway air dispersion modeling
*
Roadway noise
Roadway noise is the collective sound energy emanating from motor vehicles. It consists chiefly of road surface, tire, engine/transmission, aerodynamic, and braking elements. Noise of rolling tires driving on pavement is found to be the biggest ...
* Toll road
* Undivided highway, Undivided highway (single carriageway)
By country
* Algeria East–West Highway
* Autobahns of Austria
* ''Autoput'' and ''Autocesta''
* ''Rodovia''
* ''Avtomagistrala''
* Controlled-access highway#Canada, Highways in Canada
* Expressways of China, Expressway
* ''Autocesta''
* ''Dálnice''
* ''Autostrada''
* ''Autoroutes of France, Autoroute''
* Autobahns of Germany
* ''Aftokinitodromos''
* ''Autópálya''
* National Highway (India), National Highways and Expressways of India, Expressways
* Motorway (Ireland), Motorway
* List of highways in Israel
* Autostrade of Italy
* ''Expressways of Japan, Kōsokudōro''
* ''Malaysian expressway system, Lebuhraya''
* ''Mexican Federal Highway, Autopista de Carretera Federal''
* ''Autoroutes of Morocco, Autoroute''
* ''Avtopat''
* ''Motorvei''
* Motorways of Pakistan, Motorways and National Highways of Pakistan
* ''Autoestrada''
[Notable for the introduction of the world's first electronic toll collection system, the ''Via Verde''.]
* Russian federal highways
* ''Autoput''
* ''Avtocesta''
* ''Highways in Spain, Autopista''
* ''Motorväg''
* Autobahns of Switzerland
* Highway system in Taiwan, Freeways in Taiwan
* Thai highway network
* State Highways (Ukraine)
* Highways in the United Kingdom
* ''Autofamba''
References
External links
Full list of Euroroutes with distancesThe Greenroads Rating SystemProposed Trans-Global HighwayEuroroutes with distancesOntario Super Highway Program (June 19, 2011)Video of Highway 401 through Greater Toronto
{{Authority control
Highways,
Road infrastructure
Types of roads