U.S. Route 220 (US 220) is a part of the U.S. Highway System that runs from Rockingham, North Carolina, to South Waverly, Pennsylvania.

Known as McMullen Highway for much of its length in Maryland, US 220 is the primary north–south route in central Allegany County, connecting Cumberland with its southern suburbs and Keyser, West Virginia, to the south and Bedford, Pennsylvania, to the north.

Both the northern and southern portions of the federal highway were reconstructed in the 1940s and 1950s, including a new bridge over the North Branch Potomac River.

US 220 enters Maryland in southwestern Allegany County, crossing the North Branch Potomac River and its own old alignment on a bridge from Keyser to McCoole.

The highway meets the eastern terminus of MD 135 (Paxton Street) before gaining a climbing lane and ascending a hill.

US 220 splits away from the railroad tracks to follow the valley of Deep Hollow Creek between Fort Hill immediately to the east and Dans Mountain further to the west.

After passing another curve of old alignment designated MD 830B, US 220 leaves Fort Hill and Mill Run behind.

[1][4] US 220 passes through the villages of Rawlings and Bier before intersecting the western end of MD 956 (Patriot Parkway) near Pinto.

The federal highway enters Cresaptown, where US 220 intersects MD 53 (Winchester Road), which is also the southern terminus of US 220 Truck.

[1][4] After crossing Warrior Run, Haystack Mountain flanks US 220 to the west as the federal highway passes through Amcelle, the former site of the Celanese chemical plant that is now the location of the North Branch Correctional Institution.

After passing the Upper Potomac Industrial Park, US 220 parallels CSX's Mountain Subdivision again before entering the city of Cumberland, where the highway is municipally-maintained.

Shortly after, US 220 passes east of a park and ride lot before it meets I-68 and US 40 (National Freeway) at Exit 42.

[19][20] A second round of widening occurred during World War II as a military access project; the highway was expanded to at least 24 feet (7.3 m) in width from Cumberland to Pinto to improve access to the many wartime manufacturing centers along the highway, including the Allegany Ordnance Plant in West Virginia across the Potomac River from Pinto.

The proposed routing would involve MD 53 between I-68 and Cresaptown, and is part of a larger study of a highway to connect Cumberland with Corridor H near Scherr, West Virginia.