Until the mid-1980s , SR 17 extended from its current southern terminus at State Route 1 in Santa Cruz through Oakland and across the Richmond-San Rafael Bridge to San Rafael . The roadway still exists ( apart from the 1.6 mile-long Cypress Freeway in Oakland , which had collapsed during the 1989 Loma Prieta earthquake ) but parts have been redesignated . The section between Interstate 80 and US 101 in San Rafael was renumbered as an extension of Interstate 580 . Prior to the redesignation , this part of SR 17 followed Richmond streets , including an expressway called Hoffman Boulevard , to the bridge ; a freeway built to Interstate standards was completed in 1990 after the corridor became 580 's northwestern leg . Additionally , SR 17 between Interstate 280 in San Jose and the freeway 's new northern terminus in Oakland was re-designated as Interstate 880 later that year . Since the late 1990s , an infamous misconception for some commuters and businesses in San Jose , Campbell , and Los Gatos is that SR 85 serves as the northern terminus of SR 17 and the southern terminus of I-880 . Although not planned , it is possible to truncate SR 17 further to SR 85 due to the segment meeting interstate standards as well as I-880 still terminating at its parent interstate , I-80 , in Oakland
1989 Loma Prieta earthquake
1989 Loma Prieta earthquake
California State Route 17