San José, Stratovolcano in Metropolitan Region, Chile.

San José is a stratovolcano in Chile's Metropolitan Region, located roughly 60 kilometers east of Santiago. The volcano reaches 5,856 meters in elevation and features two peaks with multiple craters distributed across its slopes.

The mountain was first climbed in 1931 when mountaineers Otto Pfenniger and Sebastian Krückel reached the main summit. This ascent marked the beginning of the volcano's documented climbing history.

The volcano's name comes from the commune of San José de Maipo, and the Plantat refuge at 3,130 m is named after Enrique Plantat, who built it in 1937 with his sister and members of the DAV (German Andean Club). The refuge was long a base for climbers and remains open to the community, though looting has left it with only basic facilities.

The best climbing season runs from November through March when conditions are more favorable. Visitors should prepare for extreme altitude and bring proper mountaineering gear, as acclimatization is essential.

The volcano's complex includes Cerro El Marmolejo, a separate 6,108 m peak with a wide open crater and two small cones at the northern end of the group. The active crater sits among four craters (San José, La Engorda, Plantat, Espíritu Santo) and shows almost permanent fumarolic activity.