camp anza was a united states army installation in what is now riverside, california during world war ii. construction began on july 3, 1942, and was completed on february 15, 1943. camp was named after juan bautista de anza, who camped near the site in 1774. the us army purchased the 1,240 acres site from the willits j. hole ranch (1910-1942), as barley and wheat farm, before 1910 the land was part of rancho la sierra (1797-1910).