Mount Oso

Mount Oso is a summit in the Diablo Ranges located in western Stanislaus County, reaching approximately 3,350 feet. The mountain sits on private property with gates controlling access to the hiking trails that lead up the slopes.

The mountain was documented by Spanish explorers during early nineteenth-century expeditions through the region. Its role as a prominent landmark has been recognized for generations as a defining feature of the local landscape.

The mountain serves as a local landmark that residents recognize and reference in daily directions and regional identity. People view it as a defining feature of the valley landscape and point to it when describing where they live.

Visiting requires advance permission since the mountain sits on private property with restricted access points. Plan your trip ahead and contact the property owners beforehand, as conditions and access availability can change throughout the year.

The summit holds broadcasting equipment and an abandoned fire observation tower from an earlier era. This historic structure reflects how the hilltop once served as a vantage point for monitoring the surrounding landscape for wildfires.

Location: California

GPS coordinates: 37.50743,-121.37438

Latest update: December 14, 2025 14:22