Alum Rock Park, in the Alum Rock district of San Jose, California, is California's oldest municipal park, established in 1872 but serving as public land since the pueblo was established in 1777. Located in a valley in the Diablo Range foothills on the east side of San Jose, the 720 acre (2.9 km2) park offers 13 miles (21 km) of trails, varying from fairly level along Penitencia Creek to sharp switchbacks climbing to the ridges to the South Rim Trail and the North Rim Trail. The narrow floor of the valley includes a visitor center, a small museum/animal rehab facility, picnic areas, playgrounds, lawns, sand volleyball pits, mineral springs, lush plant life, woodlands, creek play opportunities, and occasional group camping.

Alum Rock is a district of San Jose, California, located in East San Jose. Formerly an independent town, it has been a neighborhood of San Jose since the 1950s, though some portions are still unincorporated as a census-designated place. Alum Rock is one of San Jose's most notable and historic Chicano/Mexican-American districts. It is home to Alum Rock Park, the oldest municipal park in California and one of the largest in the country.