Personal rapid transit (PRT), also referred to as podcars or guided/railed taxis, is a public transport mode featuring a network of specially built guideways on which ride small automated vehicles that carry few (generally less than 6) passengers per vehicle. PRT is a type of automated guideway transit (AGT), a class of system which also includes larger vehicles all the way to small subway systems. In terms of routing, it tends towards personal public transport systems.
PRT vehicles are sized for individual or small group travel, typically carrying no more than three to six passengers per vehicle. Guideways are arranged in a network topology, with all stations located on sidings, and with frequent merge/diverge points. This allows for nonstop, point-to-point travel, bypassing all intermediate stations. The point-to-point service has been compared to a taxi or a horizontal lift (elevator).
Numerous PRT systems have been proposed but most have not been implemented. , only a handful of PRT systems are operational: Morgantown Personal Rapid Transit (the oldest and most extensive), in Morgantown, West Virginia, has been in continuous operation since 1975. Since 2010 a 10-vehicle 2getthere system has operated at Masdar City, UAE, and since 2011 a 21-vehicle Ultra PRT system has run at London Heathrow Airport. A 40-vehicle Vectus system with in-line stations officially opened in Suncheon, South Korea, in April 2014.Masdar City and Suncheon have only two passenger stations while at Heathrow the two stations at the carpark are very close to one another. Masdar also has three freight stations. A PRT system connecting the terminals and parking has been built at Chengdu Tianfu International Airport, but as of 2026 remain non-operational, five years after the airport opened.
Overview Most mass transit systems move people in groups over scheduled routes. This has inherent inefficiencies. For passengers, time is wasted by waiting for the next vehicle to arrive, indirect routes to their destination, stopping for passengers with other destinations, and often confusing or inconsistent schedules. Slowing and accelerating large weights can undermine public transport's benefit to the environment while slowing other traffic.
Personal rapid transit systems attempt to eliminate these wastes by moving small groups nonstop in automated vehicles on fixed tracks. Passengers can ideally board a pod immediately upon arriving at a station, and can – with a sufficiently extensive network of tracks – take relatively direct routes to their destination without stops.
The low weight of PRT's small vehicles allows smaller guideways and support structures than mass transit systems like light rail. The smaller structures translate into lower construction costs, smaller easements, and less visually obtrusive infrastructure.
As it stands, a citywide deployment with many lines and closely spaced stations, as envisioned by proponents, has yet to be constructed. Past projects have failed because of financing, cost overruns, regulatory conflicts, political issues, misapplied technology, and flaws in design, engineering or review.
However, the theory remains active. For example, from 2002 to 2005, the EDICT project, sponsored by the European Union, conducted a study on the feasibility of PRT in four European cities. The study involved 12 research organizations, and concluded that PRT: would provide future cities "a highly accessible, user-responsive, environmentally friendly transport system which offers a sustainable and economic solution." could "cover its operating costs, and provide a return which could pay for most, if not all, of its capital costs." would provide "a level of service which is superior to that available from conventional public transport." would be "well received by the public, both public transport and car users." The report also concluded that, despite these advantages, public authorities will not commit to building PRT because of the risks associated with being the first public implementation.EDICT Final Report (PDF)" from cardiff.gov.uk
+Comparison of personal rapid transit with existing transport systemsSimilar to cars / automobiles Vehicles are small—typically two to six passengers Vehicles are individually hired, like taxis, and shared only with the passengers of one's choosing Vehicles travel along a network of guideways, much like a network of streets. Travel is point-to-point, with no intermediate stops or transfers Potential for on-demand, around-the-clock availability Stops are designed to be off the main guideway, allowing through traffic to bypass stations unimpededSimilar to trams, buses, and monorails A public amenity (although not necessarily publicly owned), shared by multiple users Reduced local pollution (electric powered) Passengers embark and disembark at discrete stations, analogous to bus stops or taxi standsSimilar to automated people movers Fully automated, including vehicle control, routing, and collection of fares Usually above the street—typically elevated—reducing land usage and congestionDistinct features Vehicle movements may be coordinated, unlike the autonomous human control of cars and bikes Small vehicle size allows infrastructure to be smaller than other transit modes Automated vehicles can travel close together. Possibilities include dynamically combined "trains" of vehicles, separated by a few inches, to reduce drag and increase speed, energy efficiency and passenger density
The PRT acronym was introduced formally in 1978 by J. Edward Anderson.J. Edward Anderson, "What is Personal Rapid Transit?" , University of Washington, 1978 The Advanced Transit Association (ATRA), a group which advocates the use of technological solutions to transit problems, compiled a definition in 1988 that can be seen here.
List of operational automated transit networks (ATN) systems Currently, five advanced transit networks (ATN) systems are operational, and several more are in the planning stage.
System Manufacturer Type Locations Length Notes Morgantown PRT Boeing GRT Morgantown, West Virginia, US (1975) 5 / 73 Up to 20 passengers per vehicle, some rides not point-to-point during low usage periods ParkShuttle 2getthere GRT Rivium, the Netherlands (November 2005) 1.8 km (1.1 mi) 5 2nd generation GRT (Group Rapid Transit) vehicles accommodate up to 24 passengers (12 seated). The vehicles operate on-schedule during peak hours, at a 2.5 minute interval, and can operate on demand during off-peak hours. The current system will operate until the end of 2018, after which it is expected to be replaced and expanded.. I pilot scheme operated on part of the current route between 1999 and 2005. CyberCab 2getthereMogge, John, The Technology of Personal Transit, "Figure 6. MASDAR Phase 1A Prototype Passenger PRT." Paper delivered at the World Future Energy Summit, January 20, 2009. Available in WFES online media center. PRT Masdar City, Abu Dhabi, UAE (November 2010) 2/10 passenger, (3/3 freight, not put into service) Initial plans called for cars to be banned, with PRT as the only powered intra-city transportWWF, Abu Dhabi unveil plans for sustainable city. World Wildlife Fund, January 13, 2008 (along with an inter-city light rail lineDesert state channels oil wealth into world's first sustainable city). The Guardian, January 21, 2008.). In October 2010 it was announced the PRT would not expand beyond the pilot scheme due to the cost of creating the undercroft to segregate the system from pedestrian traffic. Plans now include electric cars and electric buses. In June 2013 a representative of the builder 2getthere said the freight vehicles had still not been put into service because they had not worked out how to get freight to and from the stations. Ultra PRT Heathrow pod PRT Heathrow Airport, England, UK (June 2011) BAA: Heathrow Transit System a World First , 18 December 2007 3 / 21 The Heathrow PRT system became operational in 2011, connecting Terminal 5 with a long-term car park. In May 2014 BAA said in a draft 5-year plan that it would extend the system throughout the airport, but this was dropped from the final plan. SkycubePosco will help realize new rapid transit plan, Joong Ang Daily, 26 September 2009 Vectus PRT Suncheon, South Korea (September 2013) 2 / 40 Connects the site of 2013 Suncheon Garden Expo Korea to a station in the wetlands "Buffer Area" next to the Suncheon Literature Museum; the line runs parallel to the Suncheon-dong Stream. Stations are "on-line."
In addition, one PRT has completed construction but has not been commissioned.
System Manufacturer Type Locations Length Notes Ultra PRT Kunming Shipbuilding EquipmentPRT Tianfu Airport, Chengdu, China3 / 22Connects the airport terminal to the parking lots. While the airport opened in 2021, , the PRT has not been opened to the public.
List of ATN suppliers
The following list summarizes several well-known automated transit networks (ATN) suppliers as of 2014, with subsequent amendments.
Revenue service: Boeing (Morgantown PRT), Heathrow pod, 2getthere, Vectus. Full test track: Modutram, Cabinentaxi, Glydways, Urbanloop Historical: CVS, Aramis, PRT2000 (Raytheon), Monocab/ROMAG, EcoMobility, Tubenet Transit Systems
History
Origins Modern PRT concepts began around 1953 when Donn Fichter, a city transportation planner, began research on PRT and alternative transportation methods. In 1964, Fichter published a book which proposed an automated public transit system for areas of medium to low population density. One of the key points made in the book was Fichter's belief that people would not leave their cars in favor of public transit unless the system offered flexibility and end-to-end transit times that were much better than existing systems – flexibility and performance he felt only a PRT system could provide. Several other urban and transit planners also wrote on the topic and some early experimentation followed, but PRT remained relatively unknown.
Around the same time, Edward Haltom was studying monorail systems. Haltom noticed that the time to start and stop a conventional large monorail train, like those of the Wuppertal Schwebebahn, meant that a single line could only support between 20 and 40 vehicles an hour. In order to get reasonable passenger movements on such a system, the trains had to be large enough to carry hundreds of passengers (see headway for a general discussion). This, in turn, demanded large guideways that could support the weight of these large vehicles, driving up capital costs to the point where he considered them unattractive.Anderson
Haltom turned his attention to developing a system that could operate with shorter timings, thereby allowing the individual cars to be smaller while preserving the same overall route capacity. Smaller cars would mean less weight at any given point, which meant smaller and less expensive guideways. To eliminate the backup at stations, the system used "offline" stations that allowed the mainline traffic to bypass the stopped vehicles. He designed the Monocab system using six-passenger cars suspended on wheels from an overhead guideway. Like most suspended systems, it suffered from the problem of difficult switching arrangements. Since the car rode on a rail, switching from one path to another required the rail to be moved, a slow process that limited the possible headways.
UMTA is formed