Tilden Regional Park, also known as Tilden Park, is a 2,079-acre regional park in the East Bay, part of the San Francisco Bay Area in California. It is between the Berkeley Hills and San Pablo Ridge. In addition to major areas of wilderness, the park includes several developed features, including environmental education areas, extensive botanical garden, swimming lake, golf course, model farm, miniature train, merry-go-round, and event venue. Lake Anza is located in the central portion of Tilden Regional Park and is open for swimming from May to September. The swim beach is open May–September while hiking trails and picnic areas are open year-round. Founded in 1936 from former watershed lands, Tilden is one of the East Bay Regional Park District’s three original parks. It was named after Charles Lee Tilden, president of the District’s First Board of Directors. Workers from the Works Progress Administration built much of the park’s infrastructure during the Great Depression. Tilden’s 2,079 acres feature the iconic carousel, steam train, botanical gardens, Little Farm, Environmental Education Center, redwood groves, picturesque views of the bay, picnic areas, and seasonal swimming at Lake Anza.