California State Route 17

Looking downhill from the Summit Road overpass; brake lights can be seen as cars slow down in anticipation of the tight curves ahead.

California Highway 17 is a divided highway that runs between San Jose, California and Santa Cruz, California. Much of its length goes through the Santa Cruz Mountains, where the four-lane highway twists and turns along switchbacks between the Santa Clara Valley to a summit point and then back nearly to sea level in Santa Cruz. From Los Gatos to the northern terminus in San Jose, the highway expands to as many as 8 lanes. Highway 17 carries substantial commuter and vacation traffic between San Jose and Santa Cruz, and the combination of narrow shoulders, dense and high-speed traffic, sharp turns, and sudden changes in traffic speeds makes it one of the most dangerous highways in California.

Until 1983, Highway 17 extended from its current southern terminus at California State Route 1 in Santa Cruz through Oakland and across the Richmond-San Rafael Bridge to San Rafael, California. The roadway still exists; however, the section between Interstate 80 and San Rafael was renamed as an extension of Interstate 580. Additionally, Highway 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.