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 (211 kilometers) of track, including eBART, a 9-mile (14 km) spur line running to Antioch, and Oakland Airport Connector, a 3-mile (4.8 km) automated guideway transit line serving Oakland San Francisco Bay Airport. With an average of 179,900 weekday passenger trips as of the third quarter of 2025 and 50,791,900 annual passenger trips in 2024, BART is the seventh-busiest rapid transit system in the United States.
BART is operated by the San Francisco Bay Area Rapid Transit District which formed in 1957. The initial system opened in stages from 1972 to 1974.