Plaster City, California is a company town with a large gypsum quarry and plant owned by United States Gypsum in Imperial County, California. It is located 17 miles west of El Centro, at an elevation of 105 feet, a two-hour drive south of Palm Springs, or a 90 minute drive east from San Diego. The quarry and supporting railroad were started in 1920 by Imperial Valley Gypsum and Oil Corporation founder Samuel Dunnaway, a pharmacist from San Diego, then acquired by United States Gypsum in 1945.