In the 18th century , a trail across the pass formed part of the historic El Camino Real connecting Mission Santa Clara de Asís with Mission Santa Cruz , likely along a route followed earlier by Native Americans . Lakes near the summit made the place a popular fishing and swimming spot until the 1906 San Francisco earthquake caused them to dry up . In 1940 , State Route 17 replaced the Soquel San Jose Road through the pass ; the old alignment still crosses the pass , a short distance to the east of State Route 17 , as the Old Santa Cruz Highway . A Southern Pacific passenger train line through the pass , from Los Gatos to Olympia , opened in 1880 but closed again after storms in early 1940 caused mudslides and washouts on the line
1906 San Francisco earthquake
1906 San Francisco earthquake
Patchen Pass