The Washington and Old Dominion Railroad (colloquially referred to as the W&OD), the successor to the bankrupt Washington and Old Dominion Railway, was an intrastate short-line railroad located in Northern Virginia. Its oldest line extended from Alexandria on the Potomac River northwest to Bluemont at the foot of the Blue Ridge Mountains near Snickers Gap, not far from the boundary line between Virginia and West Virginia. The railroad's route largely paralleled the routes of the Potomac River and the present Virginia State Route 7 (VA Route 7).