Sierra Azul Open Space Preserve

Sierra Azul Open Space Preserve is a protected area spanning nearly 20,000 acres of natural landscape, including wooded canyons, chaparral hills, meadows, and mountain peaks. The terrain encompasses diverse ecosystems, with each zone supporting different plants and wildlife adapted to its conditions.

This land was developed as a military site when a radar station was built on the highest peak during the Cold War to monitor airspace. The facility was decommissioned decades later, leading to the land's conversion into a public nature preserve.

Mount Umunhum holds sacred meaning for the Amah Mutsun people, its name coming from their language and referring to a hummingbird's resting place. Visitors walking these trails are moving through a landscape that remains spiritually important to the descendants of the region's first inhabitants.

The preserve has a network of trails that visitors can explore, accessible from several entry points where parking is available. Arriving early is recommended, especially on weekends, as the area becomes crowded during good weather.

Two major water sources originate within the preserve and flow downhill toward reservoirs that supply the region. Recognizing these natural springs offers visitors insight into the water cycle that feeds the valley below.

Location: California

GPS coordinates: 37.16861,-121.26167

Latest update: December 12, 2025 17:44