Camp Anza was a United States Army installation, in Riverside, California, during World War II. Construction began on July 3, 1942, and was completed on February 15, 1943. The camp was named after Juan Bautista de Anza, an early explorer who camped near the site in 1774. The US Army purchased the 1,240-acre site from the Willits J. Hole Ranch (1910–1942), a barley and wheat farm. Before 1910 the land was part of Rancho La Sierra (1797–1910).