Earp, California is an unincorporated community in San Bernardino County in the Sonoran Desert close to the California/Arizona state line at the Colorado River in Parker Valley. The town, originally named Drennan in 1910, was renamed Earp in 1929. It was named for famed Old West lawman Wyatt Earp who with his common-law wife, Josephine Sara…Earp, California is an unincorporated community in San Bernardino County in the Sonoran Desert close to the California/Arizona state line at the Colorado River in Parker Valley. The town, originally named Drennan in 1910, was renamed Earp in 1929. It was named for famed Old West lawman Wyatt Earp who with his common-law wife, Josephine Sarah Marcus, lived part-time in the area beginning in 1906. Earp staked more than 100 copper and gold mining claims near the base of the Whipple Mountains.