U.S. Route 48 (US 48), also known as the incomplete Corridor H of the Appalachian Development Highway System, extends from Interstate 79 (I-79) in Weston, West Virginia, eastward across the crest of the Allegheny Mountains to I-81 in Strasburg, Virginia. It is planned to extend 157 miles (253 km) from northwestern Virginia to central West Virginia. Two previous highways were designated as US 48. The first, in California, was incorporated into the route of US 50; the second, in western Maryland and West Virginia, was redesignated Interstate 68.