The Northern Neck is the northernmost of three peninsulas on the western shore of the Chesapeake Bay in the Commonwealth of Virginia(along with the Middle Peninsula and the Virginia Peninsula). The Potomac River forms the northern boundary of the peninsula; the Rappahannock River demarcates it on the south. The land between these rivers was formed into Northumberland County in 1648, prior to the creation of Westmoreland County and Lancaster County.

The Virginia Peninsula is a peninsula in southeast Virginia, bounded by the York River, James River, Hampton Roads and Chesapeake Bay. It is sometimes known as the Lower Peninsula to distinguish it from two other peninsulas to the north, the Middle Peninsula and the Northern Neck.