The South Anna River is a principal tributary of the Pamunkey River, about long, in central Virginia in the United States. Via the Pamunkey and York rivers, it is part of the watershed of Chesapeake Bay. According to the Geographic Names Information System, it has also been known as the Anna River. Course The South Anna River rises near Gordonsville in southwestern Orange County and flows generally southeastwardly and eastwardly through Louisa and Hanover counties. It joins the North Anna River to form the Pamunkey River about northeast of Ashland. Near its mouth the river collects the Newfound River. See also List of Virginia rivers References Columbia Gazetteer of North America entry DeLorme (2005). Virginia Atlas & Gazetteer. Yarmouth, Maine: DeLorme. . Rivers of Virginia Tributaries of the York River (Virginia) Rivers of Hanover County, Virginia Rivers of Louisa County, Virginia Rivers of Orange County, Virginia Rivers of Richmond, Virginia