The San Francisco Municipal Railway (Muni) opened its K line along with the Twin Peaks Tunnel on February 3, 1918. The line ran from St. Francis Circle station along West Portal Avenue, through the tunnel, along Market Street to Van Ness Avenue (joining the J Church at Church Street). And along existing tracks on Van Ness Avenue to Pine Street. On June 1, 1918, the J and K lines were removed from Van Ness Avenue and went further along Market Street to a loop at the Ferry Building.