West Virginia Route 9 (WV 9) is a major east-west state highway located in the eastern extents of West Virginia's Eastern Panhandle. The western terminus of the route is at the Maryland state line north of Paw Paw, where WV 9 becomes Maryland Route 51 (MD 51) upon crossing the Potomac River. The eastern terminus is at the Virginia state line at Keyes Gap near Mannings, West Virginia, where WV 9 continues onward as Virginia State Route 9 (SR 9).