Mount Umunhum, one of the highest peaks in California’s Santa Cruz Mountains, unites Indigenous heritage, unusual geology, Cold War history, and restored public access. Its Ohlone name means “Resting Place of the Hummingbird,” and it remains important to Native descendants, including the Amah Mutsun tribal band, who gained an easement for ceremonies and a garden. The mountain exposes a notable section of Coast Range Ophiolite uplifted near a bend in the San Andreas Fault. Its summit is dominated by the Cube, a former Air Force radar tower built in 1962. After cleanup and preservation work, the summit reopened in stages, while the mountain also continues serving as a communications site.