2015 Map of Pacheco Pass

About this map

Pacheco Pass serves as the focal point for this 2015 survey of the boundary between Santa Clara and Merced Counties. The landscape is dominated by the sprawling San Luis Reservoir and the winding course of Route 152, which cuts through the Diablo Range. The map reveals a concentration of small water features and family-named landmarks that suggest the area's history as a ranching and transit corridor. To the south, numerous springs such as Sunburnt Spring and Langston Spring are scattered across the high ground near Wolf Lake and Mammoth Lake. The presence of distinctive names like Whisky Flat, Pigs Bath Tub, and Frenchs Flat offers local-history enthusiasts a clear look at the vernacular geography of these ridges before the modern era of reservoir management.