Sierra Azul Open Space Preserve

The preserve is named for the Sierra Azul or "Blue Mountains", the name the colonizing Spanish used for the half of the Santa Cruz Mountains south of today's California Highway 17.

[7] El Sombroso is about 2 miles (3.2 km) north by northeast of Mount Umunhum.

The preserve protects the upper watersheds of two important tributaries of the Guadalupe River.

The upper headwaters of Los Gatos Creek originate just south of Loma Prieta, wrapping around the preserve on the western side before emptying into Lexington Reservoir.

The terrain varies from wooded creek canyons to chaparral hills with views to open meadows.

View overlooking Cherry Springs Pond, the origin of Cherry Springs Creek, a tributary to Hicks Creek , and thence to Guadalupe Creek