- Western Terminus:
- Virginia-West Virginia state line
- Eastern Terminus:
- Lee Highway (US 29) in Gainesville
- 42.42 miles
- Frederick, Shenandoah, Warren, Fauquier, Prince William
VA 55 is an east/west route in the Shenandoah Valley. In most areas, it is known as John Marshall Highway, although it takes on a number of local names at various points. WV 55 turns into VA 55 at the state line. It is multiplexed with US 48 from West Virginia until I-81, where US 48 ends. This section is intended to be widened to a large divided highway as a continuation of Corridor H of the Appalachian Development Highway System in West Virginia. East of I-81, VA 55 runs next to I-66 and serves as its local alternative. Almost all of VA 55 is a two-lane undivided road, although there is a section in Front Royal where it is multiplexed with US 522/US 340 as a four-lane road.