Is there subway trains in San Francisco?

Yes, San Francisco has a subway system called the Muni Metro. It is operated by the San Francisco Municipal Transportation Agency (SFMTA) and consists of five lines: the N-Judah, the T-Third Street, the K-Ingleside, the L-Taraval, and the M-Ocean View. The Muni Metro is part of a larger public transportation network that includes buses, cable cars, and historic streetcars.