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. The park is dominated by San Bruno Mountain which is a 4 miles (6.4 km) ridge. The park provides habitat for several species of rare and endangeredplants and butterflies, including the Mission blue butterfly. Trails to the summit afford views of San Francisco and the Bay Area.