The Puerto Rico Integrated Transportation Authority (PRITA) or Autori-dad de Tránsporte Integrado (ATI), serves the San Juan Urbanized Area through heavy rail and bus public transportation. The Tren Urbano (English: Urban Train) is a 10.7-mile (17.2 km) fully automated rapid transit system that serves the municipalities of San Juan, Guaynabo and Bayamón in Puerto Rico. The Tren Urbano consists of 16 stations operating on 10.7 miles (17.2 km) of track along a single line. Tren Urbano is the Caribbean's first rapid transit system.

The Mass Transit Railway (MTR) is a major public transport network serving Hong Kong. Operated by the MTR Corporation Limited (MTRCL), it consists of heavy rail, light rail, and feeder bus service centred on an 11-line rapid transit network serving the urbanised areas of Hong Kong Island, Kowloon, and the New Territories. The system included 230.9 km (143.5 mi) of rail in 2018 with 163 stations, including 95 heavy rail stations and 68 light rail stops. The MTR is one of the most profitable metro systems in the world; it had a farebox recovery ratio of 187 per cent in 2015, the world's highest. The MTR was ranked the number one metro system in the world by CNN in 2017.

The Chicago Transit Authority (CTA) operates the nation's second largest public transportation system and covers the City of Chicago and 35 surrounding suburbs. On an average weekday, approximately 1.6 million rides are taken on the CTA.

The CTA is an independent governmental agency created by state legislation. It began operating on October 1, 1947, after acquiring the properties of the Chicago Rapid Transit Company and the Chicago Surface Lines. On October 1, 1952, CTA became the sole operator of Chicago transit when it purchased the Chicago Motor Coach system.

The Massachusetts Bay Transportation Authority (abbreviated MBTA and known colloquially as "the T") is the public agency responsible for operating most public transportation services in Greater Boston, Massachusetts. Earlier modes of public transportation in Boston were independently owned and operated; many were first folded into a single agency with the formation of the Metropolitan Transit Authority (MTA) in 1947. The MTA was replaced in 1964 with the present-day MBTA, which was established as an individual department within the Commonwealth of Massachusetts before becoming a division of the Massachusetts Department of Transportation (MassDOT) in 2009.

Transport for London (TfL) is a local government body responsible for the transport system in Greater London, England.TfL has responsibility for London's network of principal road routes, for various rail networks including the London Underground, London Overground, Docklands Light Railway and TfL Rail. It does not control National Rail services in London, however, but does for London's trams, buses and taxis, for cycling provision, and for river services. The underlying services are provided by a mixture of wholly owned subsidiary companies (principally London Underground), by private sector franchisees (the remaining rail services, trams and most buses) and by licensees (some buses, taxis and river services). TfL is also responsible, jointly with the national Department for Transport (DfT), for commissioning the construction of the new Crossrail line, and will be responsible for franchising its operation once completed.