Muni Metro

Muni Metro is a light rail system serving San Francisco, California, United States, operated by the San Francisco Municipal Railway (Muni).
History.
Market Street subway.
On February 18, 1980, the Muni Metro officially began. It started with weekday N line service in the subway. The Metro service was put in phases. The subway was served only on weekdays until 1982. The K Ingleside line began using the entire Metro subway on weekdays on June 11, 1980, the L Taraval and M Ocean View lines on December 17, 1980, and the J Church line on June 17, 1981. Meanwhile, weekend service on all five lines (J, K, L, M, N) continued to use PCC streetcars operating on the surface of Market Street to the Transbay Terminal. The Muni Metro was closed on weekends. At the end of the service day September 19, 1982, streetcar operations on the surface of Market Street were discontinued entirely. The remaining PCCs taken out of service, and weekend service on the five light rail lines switch to buses for a while. Finally, on November 20, 1982, the Muni Metro subway began operating seven days a week.
Routes.
, the L Taraval is replaced by bus service, while other routes have resumed rail operation.
Operations.
Muni Metro runs from approximately 5 am to 1 am weekdays, with later start times of 7 am on Saturday and 8 am on Sunday. Owl service, or late-night service, is operated on much of the L and N lines by buses that show the same route designation.