Monte Bello Open Space Preserve is a 3,133-acre (12.68 km2) open space preserve, located near Palo Alto in the Santa Cruz Mountains, in San Mateo and Santa Clara Counties, California, United States. The preserve encompasses the upper Stevens Creek watershed in the valley between Monte Bello Ridge and Skyline Ridge. "Monte Bello" means "beautiful mountain" in Italian, and refers to Black Mountain which is the highest part of Montebello Ridge.[1] The straight valley of upper Stevens Creek is also the rift valley of the San Andreas Fault.