San Bruno Mountain State Park, officially San Bruno Mountain State and County Park, is a park located in northern San Mateo County, California. It is adjacent to the southern boundary of San Francisco and borders the cities of Brisbane, South San Francisco, Colma and Daly City. San Bruno Mountain State Park is a landmark of local and regional significance, standing as a unique open-space island in the midst of the peninsula's urbanization at the northern end of the Santa Cruz Mountain Range.