Essex County is a county located in the Middle Peninsula in the U.S. state of Virginia; the peninsula is bordered by the Rappahannock River on the north and King and Queen County on the south. As of the 2020 census, the population was 10,599. Its county seat is Tappahannock.

The Rappahannock River is a river in eastern Virginia, in the United States, approximately 195 miles (314 km) in length. It traverses the entire northern part of the state, from the Blue Ridge Mountains in the west where it rises, across the Piedmont to the Fall Line, and onward through the coastal plain to flow into the Chesapeake Bay, south of the Potomac River.