Black Mountain is a summit on Monte Bello Ridge in the Santa Cruz Mountains of west Santa Clara County, California, south of Los Altos and Los Altos Hills, and west of Cupertino; it is within the Palo Alto city limits though not near the developed part of the city. It is located on the border between Rancho San Antonio Open Space Preserve and Monte Bello Open Space Preserve, with the summit located in the former. Early Spanish explorers commonly named tree- or chaparral-covered summits which look black in the distance Loma Prieta, from the Spanish . The Spanish also called the middle portion of the Santa Cruz Mountains the Sierra Morena meaning, extending from Half Moon Bay Road south to a gap at Lexington Reservoir, and which includes a summit called Sierra Morena. There are over 100 "Black Mountains" in California.

The Santa Cruz Mountains are a mountain range in central and Northern California, United States, constituting a part of the Pacific Coast Ranges. They form a ridge down the San Francisco Peninsula, south of San Francisco. They separate the Pacific Ocean from the San Francisco Bay and the Santa Clara Valley, and continue south to the Central Coast, bordering Monterey Bay and ending at the Salinas Valley. The range passes through the counties of San Mateo, Santa Clara, and Santa Cruz, with the Pajaro River forming the southern boundary.