A mode of transport is a solution that makes use of a certain type of vehicle, infrastructure, and operation. The transport of a person or of cargo may involve one mode or several of the modes, with the latter case being called inter-modal or multi-modal transport.[1] Each mode has its own advantages and disadvantages, and will be chosen on the basis of cost, capability, and route.[2]
Governments regulate the way the vehicles are operated, and the procedures set for this purpose, including financing, legalities, and policies.[3] In the transport industry, operations and ownership of infrastructure can bepublic,private, or apartnership between the two, depending on the country and mode.[4][5] Transport modes can be a mix of the two ownership systems, such as privately owned cars and government-ownedurban transport in cities.[6] Many internationalairlines have a mixed public-private ownership.[7]
Although humans are able to walk without infrastructure, the accessibility can be enhanced through the use of roads,sidewalks, andshared-use paths, especially when using the human power with vehicles, such asbicycles,inline skates, andwheelchairs.[17] Human-powered vehicles have been developed for difficult environments, such as snow and water, bywatercraft rowing andskiing;[18][19] even the air can be flown through withhuman-powered aircraft.[20]Personal transporters, a form of hybrid human-electric powered vehicle, have emerged in the 21st century as a form of multi-model urban transport.[21]
Elephant transporting a person and some cargo on a highway between Delhi and Jaipur, India
Animal-powered transport is the use ofworking animals for the movement of people and commodities.[22] Humans may ride some of the animals directly, use them aspack animals for carrying goods, or harness them,[23] alone or inteams, to pullsleds or wheeledvehicles. They remain useful in rough terrain that is not readily accessible by automotive-based transportation.[22]
Afixed-wing aircraft, commonly called an airplane, is a heavier-than-air craft where movement of the air in relation to the wings is used to generate lift. The term is used to distinguish this fromrotary-wing aircraft, where the movement of the lift surfaces relative to the air generates lift.[24] Agyroplane is both fixed-wing and rotary wing.[citation needed] Fixed-wing aircraft range from small trainers and recreational aircraft to largeairliners and military cargo aircraft.
Two things necessary for aircraft are air flow over the wings forlift and an apparatus forlanding. The majority of aircraft require anairport with the infrastructure for maintenance, restocking, and refueling and for the loading and unloading of crew, cargo, and passengers.[25] Manyaerodromes have takeoff and landing restrictions on weight and runway length, and so are not able to handle all types of aircraft.[26] While the vast majority of fixed-wing aircraft land and take off on land, some are capable of take-off and landing on ice, snow,[27] and calm water.[28]
Autonomous or remotely-piloted airplanes are known asunmanned aerial vehicles, or UAV. These drones can range in size from less than a metre across to a full-sized airplane.[29] They are capable of carrying a payload, and are being used for package delivery.[30]
The aircraft is the second fastest method of transport, after therocket. Commercial jets can reach up to 955 kilometres per hour (593 mph), single-engine aircraft 555 kilometres per hour (345 mph). Aviation is able to quickly transport people and limited amounts of cargo over longer distances, but incurs high costs and energy use; for short distances or in inaccessible places,helicopters can be used.[31] As of April 28, 2009,The Guardian article notes that "the WHO estimates that up to 500,000 people are on planes at any time."[32]
Anaerostat is a class of lighter-than-air aircraft that gains its lift by containing a volume of gas that has a lowerdensity than the surrounding atmosphere. These includeballoons andrigid,semi-rigid, or non-rigidairships; the last is called ablimp. Thelifting gas is typically helium, as hydrogen is highly flammable. Alternatively, heated air is used inhot air balloons andthermal airships. Aerostats can transport passengers and a payload over long distances. For example,zeppelins were used on long-ranged bombing raids duringWorld War I.[33]
Land transport covers all land-based transport systems that provide for the movement of people, goods, and services. Land transport plays a vital role in linking communities to each other. Land transport is a key factor inurban planning. It consists of two kinds, rail and road.
Rail transport consists of wheeled vehicles running on tracks, which usually consist of two parallelsteel rails, known as arailway or railroad. The rails are anchoredperpendicular toties (or sleepers) of timber, concrete, or steel, to maintain a consistent distance apart, orgauge. The rails and perpendicular beams are placed on a foundation made of concrete or compressedearth andgravel in abed of ballast.[34] Alternative methods includemonorail,[35]maglev, andhyperloop.[36]Dual gauge railways have three or four rails, allowing use by trains with two or threetrack gauges.[37] Forsteep grades, a railway can use an additional toothedrack rail for traction.[38]
A train consists of one or more connected vehicles that operate on the rails, known asrolling stock. Propulsion is commonly provided by alocomotive, which hauls a series of unpowered cars that carry passengers or freight. The locomotive can be powered bysteam,diesel,[39]gas turbine,[40] or elseelectricity supplied bytrackside systems. Some or all the cars can be powered, known as amultiple unit.[39] Atram is similar to a train, but is generally smaller, travels shorter distances, and runs on rails that are integrated into the streets. Typically a tram is electric-powered, but they have also been propelled byhorses,cables,[41]gravity,[citation needed] orpneumatics.[42] Railed vehicles move with much less friction than rubber tires on paved roads, making trains moreenergy efficient, though not as efficient as ships.[43]
Intercity trains are long-haul services connecting cities;[44] modernhigh-speed rail is capable of speeds up to 350 km/h (220 mph), but this requires specially built track.Commercial maglev transport in Shanghai runs at 460 km/h (290 mph).[45]Regional andcommuter trains feed cities from suburbs and surrounding areas, while intra-urban transport is performed by high-capacitytramways andrapid transits,[46] in many cases making up the backbone of a city's public transport.[citation needed]Freight trains traditionally usedbox cars, requiring manual loading and unloading of thecargo. Since the 1980s,container trains have become the dominant solution for general freight,[47] while large quantities of bulk are transported by dedicated rolling stock. An example of the latter are specially designedtank cars for the transport ofhazardous materials.[48]
A road is an identifiableroute, way, orpath between two or moreplaces.[49] Roads are typically smoothed,paved, or otherwise prepared to allow easy travel;[50] though they need not be, and historically many roads were simply recognizable routes without any formalconstruction ormaintenance.[51] Inurban areas, roads may pass through acity orvillage and be named asstreets, serving a dual function as urban spaceeasement and route.[52]
At least within the U.S., the most common road vehicle is the automobile;[53] a light dutywheeled passenger vehicle that carries its ownmotor. Other users of roads includebuses,trucks,motorcycles,bicycles, andpedestrians. As of 2015, there were 950 million passenger cars worldwide, with a projected total of 2.5 billion in 2050.[54] Road transport offers road users the flexibility to transfer the vehicle from one lane to the other and from one road to another according to the need and convenience. This combination of changes in location, direction, speed, and timings of travel is not available to other motorized modes of transport.[55] It is possible to provide efficient intracity door-to-door service only by road transport.
Some drawbacks are that a road system consumes large amounts of space, are costly to build and maintain (including vehicles), leads to urban congestion, and have only limited ability to achieveeconomies of scale.[55] Automobiles provide high flexibility with low capacity, but require high energy and area use, and are the main source of harmfulnoise andair pollution in cities;[56] buses allow for more efficient travel at the cost of reduced flexibility.[44] Road transport by truck is often the initial andfinal stage of freight transport.[55]
Water transport is movement by means of awatercraft—such as abarge,boat,ship, orsailboat—over a body of water, such as asea,ocean,lake,canal, orriver. The need for buoyancy is common to watercraft,[57] making thehull a critical aspect of its construction, maintenance, and appearance.
Although it is slow compared to other transport, modernsea transport is a highly efficient method of transporting large quantities of goods.Commercial vessels, nearly 35,000 in number, carried 7.4 billion tons of cargo in 2007.[63] Transport by water is significantly less costly than air transport for transcontinentalshipping;[64]short sea shipping andferries remain viable in coastal areas.[65][66]
Suborbital spaceflight is the fastest of the existing and planned transport systems from a place on Earth to a distant "other place" on Earth.[82] These rocket-propelled systems could potentially do global point-to-point transport delivery of passengers or cargo in less than 90 minutes.[83]
Bridges, such asGolden Gate Bridge, allow roads and railways to cross bodies of water.Tunnels, such as theTampere Tunnel, allow traffic to pass underground or through rock formations.
Infrastructure is the fixed installations that allow a vehicle to operate. It consists of a transport network, a terminal, and facilities for parking and maintenance.[84] For rail, pipeline, road, and cable transport, the entire way the vehicle travels must be constructed. Air and watercraft are able to avoid this, since theairway andseaway do not need to be constructed. However, they require fixed infrastructure at terminals.[85]
Terminals such as airports, ports, and stations, are locations where passengers and freight can be transferred from one vehicle or mode to another. For passenger transport, terminals are integrating different modes to allow riders, who are interchanging between modes, to take advantage of each mode's benefits[85]. For instance,airport rail links connect airports to the city centres and suburbs. The terminals for automobiles areparking lots, while buses and coaches can operate from simple stops.[86] For freight, terminals act astransshipment points,[87] though some cargo is transported directly from the point of production to the point of use.
Thefinancing of infrastructure can either bepublic orprivate. Transport is often anatural monopoly[88] and a necessity for the public; roads, and in some countries railways and airports, are funded throughtaxation. New infrastructure projects can have high costs and are often financed throughdebt. Many infrastructure owners, therefore, impose usage fees,[citation needed] such aslanding fees at airports ortoll plazas on roads.[89] Independent of this, authorities may imposetaxes on the purchase or use of vehicles.[90] Because of poor forecasting and overestimation of passenger numbers by planners, there is frequently a benefits shortfall for transport infrastructure projects.[91]
Animals used in transportation includepack animals andriding animals. These include variousbovids,equids, andcamelids; animal families noted for their muscular strength.[92] Other species employed for various forms of transport include the dog, elephant, ostrich, sheep, and even thedolphin.[93]
AFiat Uno in 2018Customized motorcycle to maximize load capacity. Mobility is important for motorcycles, which are primarily used for transporting light cargo in urban areas.
A vehicle is a non-living device that is used to move people and goods. Unlike the infrastructure, the vehicle moves along with the cargo and riders. Unless being pulled/pushed by a cable or muscle-power, the vehicle must provide its own propulsion; this is most commonly done through asteam engine,combustion engine,electric motor,[94]jet engine, orrocket,[95] though other means of propulsion also exist such as sail power orcompressed air.[96] Vehicles also need a system of converting the energy into movement; this is most commonly done throughwheels,propellers, andair pressure.[97]
Vehicles are commonly staffed by adriver. However, some systems, such aspeople movers and some rapid transits, are fullyautomated.[98] Forpassenger transport, the vehicle must have a compartment, seat, or platform for the passengers. Simple vehicles, such as automobiles, bicycles, or simple aircraft, may have one of the passengers as a driver. Since 2016, progress related to theFourth Industrial Revolution has brought a lot of new emerging technologies for transportation and automotive fields such asconnected vehicles[99] andautonomous vehicles.[100] These innovations are said to form future mobility, but concerns remain on safety and cybersecurity, particularly concerning connected and autonomous mobility.[101]
Private transport is only subject to the owner of the vehicle, who operates the vehicle themselves. For public transport and freight transport, operations are done throughprivate enterprise,governments, or a partnership between the two.[102][4] The infrastructure and vehicles may be owned and operated by the same company, or they may be operated by different entities. Traditionally, many countries have had anational airline andnational railway. Since the 1980s, many of these have beenprivatized.[103] International shipping remains a highly competitive industry with little regulation,[104] but ports can be public-owned.[105]
As thepopulation of the world increases,cities grow in size and population—according to the United Nations, 55% of the world's population live in cities, and by 2050 this number is expected to rise to 68%.[106]Public transport policy must evolve to meet the changing priorities of the urban world.[107] The institution of policy enforces a degree of order in transport, which is by nature chaotic as people attempt to travel from one place to another as rapidly as possible.[108] This policy helps to reduce accidents and save lives.
Relocation of travelers and cargo are the most common uses of transport. However, other uses exist, such as the transfer of mobile construction and emergency equipment, or the strategic and tacticalrelocation ofarmed forces duringwarfare.
Passenger transport, or travel, is divided intopublic andprivate transport. Public transport is scheduled services on fixed routes, while private service can be scheduled (e.g. commercial airlines) or chartered (e.g.shipping) or can provide ad hoc services at the riders desire (e.g. taxi).[102] The latter offers better flexibility, but has lower capacity and a higher environmental impact. Travel may be as part of dailycommuting or forbusiness, leisure, ormigration.[109]
Short-haul transport is dominated by the automobile and mass transit. The latter consists ofbuses in rural and small cities, supplemented with commuter rail, trams, andrapid transit in larger cities.[102] Long-haul transport involves the use of the automobile, trains, ships,coaches, and aircraft,[110] the last of which have become predominantly used for the longest, including intercontinental, travel.Intermodal passenger transport is where a journey is performed through the use of several modes of transport; since all human transport normally starts and ends with walking, all passenger transport can be considered intermodal.[111] Public transport may also involve the intermediate change of vehicle, within or across modes, at atransport hub, such as abus orrailway station.[112]
Taxis and buses can be found on both ends of the public transport spectrum. Buses are the cheapest mode of transport but are not necessarily flexible, and taxis are very flexible but more expensive.[113] In the middle isdemand-responsive transport, offering flexibility whilst remaining affordable.
An ambulance is a vehicle used to transport people from or between places of treatment,[115] and in some instances will also provide out-of-hospital medical care to the patient. The word is often associated with road-going "emergency ambulances", which form part ofemergency medical services, administeringemergency care to those with acute medical problems.
Air medical services is a comprehensive term covering the use of air transport to move patients to and from healthcare facilities and accident scenes. Personnel provide comprehensive prehospital and emergency and critical care to all types of patients during aeromedical evacuation or rescue operations, aboard helicopters, propeller aircraft, or jet aircraft.[116][117]
Freight transport, or shipping, is a key in thevalue chain in manufacturing.[118] With increased specialization andglobalization, production is being located further away from consumption, rapidly increasing the demand for transport.[119] Transport creates place utility by moving the goods from the place of production to the place of consumption.[120] While all modes of transport are used for cargo transport, there is high differentiation between the nature of the cargo transport, in which mode is chosen.[121]Logistics refers to the entire process of transferring products from producer to consumer, including storage, transport, transshipment, warehousing, material-handling, and packaging, with associated exchange of information.[122]Incoterm deals with the handling of payment and responsibility ofrisk during transport.[123]
Containerization, with the standardization ofISO containers on all vehicles and at all ports, has revolutionizedinternational anddomestic trade, offering a huge reduction intransshipment costs. Traditionally, all cargo had to be manually loaded and unloaded into the haul of any ship or car; containerization allows for automated handling and transfer between modes, and the standardized sizes allow for gains ineconomy of scale in vehicle operation. This has been one of the key driving factors in international trade and globalization since the 1950s.[124]
Bulk transport is common with cargo that can be handled roughly without significant deterioration; typical examples areore, coal,cereals, andpetroleum.[125] Because of the uniformity of the product, mechanical handling can allow enormous quantities to be handled quickly and efficiently. The low value of the cargo combined with high volume also means thateconomies of scale become essential in transport, and gigantic ships and whole trains are commonly used to transport bulk. Liquid products with sufficient volume may also be transported by pipeline.
Air freight has become more common for products of high value; while less than one percent of world transport by volume is by airline, it amounts to forty percent of the value. Time has become especially important in regards to principles such aspostponement andjust-in-time within the value chain, resulting in a high willingness to pay for quick delivery of key components or items of high value-to-weight ratio.[126] In addition to mail, common items sent by air includeelectronics andfashion clothing.
In thethree-sector model ofeconomics, transportation is a component of thetertiary sector that provides services for a functioning economy. Thus, the inefficiency and malfunctioning of transport creates an economic impact. Even when functioning effectively, the operation of a transportation network can have an adverse effect on the environment and human safety. For example, road traffic accidents are one of the leading causes of death world-wide, killing or injuring nearly 1.35 million people every year.[127] The planning, design, maintenance, and operation of facilities for different transport modes is performed through transportation engineering. Their goal is to provide for the safe, efficient, rapid, comfortable, convenient, economical, and environmentally compatible movement of people and goods transport.[128]
Transport is a key component of growth and globalization, such as inSeattle, Washington, United States.
Transport is a key necessity forspecialization—allowing production and consumption of products to occur at different locations. Throughout history, transport has been a spur to expansion; better transport allows moretrade and a greater spread of people.Economic growth has always been dependent on increasing the capacity and rationality of transport.[129] But the infrastructure and operation of transport have a great impact on the land, and transport is the largest drainer of energy, makingtransport sustainability a major issue.
Due to the way modern cities and communities are planned and operated, a physical distinction between home and work is usually created, forcing people to transport themselves to places of work, study, or leisure, as well as to temporarily relocate for other daily activities.[130] Passenger transport is the essence oftourism, a major part ofrecreational transport. Commerce requires the transport of people to conduct business, either to allow face-to-face communication for important decisions or to move specialists from their regular place of work to sites where they are needed.
Inlean thinking, transporting materials orwork in process from one location to another is seen as one of the seven wastes (Japanese term:muda) which do not add value to a product.[131]
The engineering of thisroundabout inBristol, United Kingdom, attempts to make traffic flow free-moving.
Because of the negative impacts incurred, transport often becomes the subject of controversy related to choice of mode, as well as increased capacity. Automotive transport can be seen as atragedy of the commons, where the flexibility and comfort for the individual deteriorate the natural and urban environment for all.[135]Density of development depends on mode of transport, with public transport allowing for better spatial use. Good land use keeps common activities close to people's homes and places higher-density development closer to transport lines and hubs, to minimize the need for transport. There areeconomies of agglomeration.[136] Beyond transport, some land uses are more efficient when clustered. Transport facilities consume land, and in cities pavement (devoted to streets and parking) can easily exceed 20 percent of the total land use.[137] An efficient transport system can reduce land waste.
Too much infrastructure and too much smoothing for maximum vehicle throughput mean that in many cities there is too much traffic and many—if not all—of the negative impacts that come with it.[citation needed] It is only in recent years[when?] that traditional practices have started to be questioned in many places; as a result of new types of analysis which bring in a much broader range of skills than those traditionally relied on—spanning such areas as environmental impact analysis, public health, sociology, and economics—the viability of the old mobility solutions is increasingly being questioned.[citation needed]
The energy levels involved in a transport accident can pose a significant risk for crew and passengers,[138] making safety an issue of importance to governments.[139] Significant accidents involve a review by law enforcement and independent investigators from a safety board,[140] such as theNTSB in the U.S. Measures and methods have been implemented to improve the safety ofroads,automobiles,motorcycles,bicycles, railways, ships, andaircraft.[141] There areemergency medical services andsea rescue measures for rapid response to transport emergencies.[142] Statistics are gathered from accidents, then analyzed and used to determine safety measures to lower the casualty rate.[143]
Transport is a major use ofenergy and burns most of the world'spetroleum. This creates air pollution, includingnitrous oxides andparticulates, and is a significant contributor toglobal warming through emission ofcarbon dioxide,[145] for which transport is the fastest-growing emission sector.[146] According to the International Energy Agency (IEA), the transportation sector accounts for more than one-third of CO2 emissions globally in the early 2020ies.[147] By sub-sector, road transport is the largest contributor to global warming.[148]Environmental regulations in developed countries have reduced individual vehicles' emissions; however, this has been offset by increases in the numbers of vehicles and in the use of each vehicle.[145] Some pathways to reduce the carbon emissions of road vehicles considerably have been studied.[149][150] Energy use and emissions vary largely between modes, causingenvironmentalists to call for a transition from air and road to rail and human-powered transport,[151] as well as increasedtransport electrification andenergy efficiency.
Other environmental impacts of transport systems includetraffic congestion and automobile-orientedurban sprawl, which can consume natural habitat and agricultural lands. By reducing transport emissions globally, it is predicted that there will be significant positive effects on Earth'sair quality,acid rain,smog, and climate change.[152]
Whileelectric cars are being built to cut downCO2 emission at the point of use, an approach that is becoming popular among cities worldwide is to prioritize public transport, bicycles, andpedestrian movement. Redirecting vehicle movement to create 20-minute neighbourhoods[153] that promotesexercise while greatly reducing vehicle dependency and pollution. Some policies are levying a congestion charge[154] to cars for travelling within congested areas during peak time.
Airplane emissions change depending on the flight distance. It takes a lot of energy to take off and land, so longer flights are more efficient per mile traveled. However, longer flights naturally use more fuel in total. Short flights produce the most CO2 per passenger mile, while long flights produce slightly less.[155][156] Things get worse when planes fly high in theatmosphere.[157][158] Their emissions trap much more heat than those released at ground level. This is not just because of CO2, but a mix of other greenhouse gases in the exhaust.[159][160] In 2022 global CO2 emissions from the transport sector grew by more than 250 Mt CO2 to nearly 8 Gt CO2, which represent more than 3% compared to 2021. Aviation was responsible for a significant part of that increase.[161]
City buses produce about 0.3 kg of CO2 for every mile traveled per passenger. For long-distance bus trips (over 20 miles), that pollution drops to about 0.08 kg of CO2 per passenger mile.[162][155] On average, commuter trains produce around 0.17 kg of CO2 for each mile traveled per passenger. Long-distance trains are slightly higher at about 0.19 kg of CO2 per passenger mile.[162][155][163] The fleet emission average for delivery vans, trucks and big rigs is 10.17 kg (22.4 lb) CO2 per gallon of diesel consumed. Delivery vans and trucks average about 7.8 mpg (or 1.3 kg of CO2 per mile) while big rigs average about 5.3 mpg (or 1.92 kg of CO2 per mile).[164][165]
The United Nations first formally recognized the role of transport insustainable development in the 1992United Nations Earth summit. In the 2012 United Nations World Conference, global leaders unanimously recognized that transport and mobility are central to achieving the sustainability targets.[166] Since then, data has been collected to show that the transport sector contributes to a quarter of the globalgreenhouse gas emissions, and thereforesustainable transport has been mainstreamed across several of the2030 Sustainable Development Goals, especially those related to food, security, health, energy, economic growth, infrastructure, and cities and human settlements. Meeting sustainable transport targets is said to be particularly important to achieving theParis Agreement.[167]
There are variousSustainable Development Goals (SDGs) that are promoting sustainable transport to meet the defined goals. These includeSDG 3 on health (increased road safety),SDG 7 on energy,SDG 8 on decent work and economic growth,SDG 9 on resilient infrastructure,SDG 11 on sustainable cities (access to transport and expanded public transport),SDG 12 on sustainable consumption and production (endingfossil fuel subsidies), and SDG 14 on oceans, seas, and marine resources.[168]
Contemporary development studies recognise transportation networks as a key element of economic development, socio-economic well-being and poverty reduction.[169] However, road network development has not always fulfilled its original intentions and has contributed significantly to environmental degradation and, in some cases, led to the loss of cultural traditions and the marginalisation of indigenous peoples.[170][171] Compared to roads, the development of air links (helicopters and planes) has had an even more devastating impact. What is more, helicopters used for tourist activities are subject to considerable criticism from a perspective of environmental protection as well as sports ethics.[171]
Humans' first ways to move included walking, running, and swimming. Thedomestication of animals introduced a new way to lay the burden of transport on more powerful creatures, allowing the hauling of heavier loads, or humans riding animals for greater speed and duration.[172] Inventions such as the wheel and the sled (U.K. sledge) helped make animal transport more efficient through the introduction ofvehicles.[173]
Water transport, including rowed and sailed vessels, dates back totime immemorial and was the only efficient way to transport large quantities or over large distances prior to theIndustrial Revolution. The first watercraft werecanoes either cut out fromtree trunks or made of animal hides.[175] Early deep water transport was accomplished with ships that were either rowed or used thewind for propulsion, or a combination of the two.[176] The importance of water has led to most cities that grew up as sites for trading being located on rivers or on the sea-shore, often at the intersection of two bodies of water.
Until the Industrial Revolution, transport remained slow and costly, and production and consumption gravitated as close to each other as feasible.[citation needed] TheIndustrial Revolution in the 19th century saw several inventions fundamentally change transport. With theoptical telegraph, communication became rapid and independent of the transport of physical objects.[177] The invention of thesteam engine, closely followed by its application inrail transport, made land transport independent of human or animal muscles.[178] Both speed and capacity increased, allowing specialization through manufacturing being located independently of natural resources. The 19th century also saw the development of thesteam ship, which sped up global transport.
With the development of thecombustion engine and the automobile around 1900, road transport became more competitive again, and mechanical private transport originated. The first "modern" highways were constructed during the 19th century withmacadam.[179][180] Later,tarmac andconcrete became the dominant paving materials.
In 1903 theWright brothers demonstrated the first successful controllableairplane, and after World War I (1914–1918) aircraft became a fast way to transport people and express goods over long distances.[181]
After World War II (1939–1945) the automobile and airlines took higher shares of transport, reducing rail and water to freight and short-haul passenger services.[182] Scientific spaceflight began in the 1950s, with rapid growth until the 1970s, when interest dwindled. In the 1950s the introduction ofcontainerization gave massive efficiency gains in freight transport, fosteringglobalization.[124] International air travel became much more accessible in the 1960s with the commercialization of thejet engine. Along with the growth in automobiles and motorways, rail and water transport declined in relative importance. After the introduction of theShinkansen in Japan in 1964, high-speed rail in Asia and Europe started attracting passengers on long-haul routes away from the airlines.[182]
In the U.S. during the 19th century,privatejoint-stockcorporations owned mostaqueducts,bridges,canals,railroads,roads, andtunnels.[183] Most such transport infrastructure came under government control in the late 19th and early 20th centuries, culminating in thenationalization of inter-city passenger rail-service with the establishment ofAmtrak.[184] However, as recently as 2010, a movement to privatize roads and other infrastructure has gained ground and adherents.[185]
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