The Potomac River flows 287 miles in a winding southeast course from its source in the Allegheny Mountains to its mouth in Chesapeake Bay. Along the way, it forms part of the border of Maryland, West Virginia, and Virginia.
The river has been long associated with American history. It breaks through the Blue Ridge Mountains at Harpers Ferry, the scene of John Brown's raid. Mount Vernon, the home of George Washington, overlooks the river 17 miles below Washington D.C. DC.