Yorkville is an unincorporated community in Mendocino County, California. It is located 7.5 miles (12 km) southwest of Hopland, at an elevation of 922 feet (281 m). The original townsite was about 3 miles (5 km) northwest of the present site at 38°54′50″N 123°15′40″W﻿ / ﻿38.91389°N 123.26111°W﻿ / 38.91389; -123.26111. The Yorkville post office opened in 1868 and moved to the new site with the town in 1937. The name honors R.H. York, the town's founder.