US 422. The portion east of Lock Haven of the remainder of the route became US 220, US 15, and US 122 ca. 1935; this alignment is now roughly followed by US 220, I-180, PA 147, and PA 61. Major intersections See also References External links Pennsylvania Highways: PA 120 Pennsylvania Highways: History of U.S. Route 120 Endpoints of historic U.S. Highway 120 at USEnds.com 1 120 Transportation in Elk County, Pennsylvania Transportation in Cameron County, Pennsylvania Transportation in Clinton County, Pennsylvania