State Route 13 (SR 13) is a state highway in the U.S. state of California. It runs entirely in Alameda County, connecting Interstate 580 in Oakland to Interstate 80/Interstate 580 in Berkeley. It consists of three contiguous segments: the Warren Freeway from I-580 to State Route 24 in Oakland; Tunnel Road, a narrow two-lane road to Claremont Avenue in Berkeley; and Ashby Avenue, a main east–west street through south Berkeley to I-80/I-580.
