Clarksville is an unincorporated community in El Dorado County, California. It is located 14 miles west-southwest of Placerville, at an elevation of 676 feet. Clarksville was established during the California gold rush and at one point had over a thousand residents and several businesses. By 1931 only twenty residents remained. Little remains t…Clarksville is an unincorporated community in El Dorado County, California. It is located 14 miles west-southwest of Placerville, at an elevation of 676 feet. Clarksville was established during the California gold rush and at one point had over a thousand residents and several businesses. By 1931 only twenty residents remained. Little remains today, but the Clarksville Heritage Society preserves the town's history.