Bay Area Rapid Transit (BART) is a rapid transit system serving the San Francisco Bay Area in California. BART serves 50 stations along six routes and 131 miles of track, including a 9-mile (14 km) spur line running to Antioch, which uses diesel multiple unit vehicles, and a 3-mile (4.8 km) automated guideway transit line serving San Francisco Bay Oakland International Airport. With an average of 160,400 weekday passengers as of the fourth quarter of 2023 and 48,119,400 annual passengers in 2023, BART is the seventh-busiest rapid transit system in the United States.
Train in southern San Francisco in July 2023
AC Transit buses at San Leandro station
Interior of a new BART car
Two BART ticket machines at Embarcadero station in San Francisco. Both have been converted to Clipper card usage only. The machine on the left dispenses new Clipper cards and adds value to existing cards, while the machine on the right only adds value to existing cards.
Rapid transit or mass rapid transit (MRT), also known as metro, is a type of high-capacity public transport that is generally built in urban areas. A rapid transit system that primarily or traditionally runs below the surface may be called a subway, tube, or underground. Unlike buses or trams, rapid transit systems are railways, usually electric, that operate on an exclusive right-of-way, which cannot be accessed by pedestrians or other vehicles. They are often grade-separated in tunnels or on elevated railways.
The London Underground is the world's first and oldest rapid transit system.
The New York City Subway is the world's largest single-operator rapid transit system by number of metro stations, at 472.
A crowded Paris Métro average station platform in 2007.
A station of the Guangzhou Metro in 2005.