US 30 originally ran along King Street through the city of Lancaster. In York, the route followed Market Street through the city. The section of US 30 to the west of York, between York and Lancaster, and to the east of Lancaster was widened to a multilane highway in the 1930s. The route was shifted to use the one-way pair of King Street eastbound and Orange Street westbound through Lancaster in the 1930s. In the 1950s, US 30 was moved to the one-way pair of Market Street eastbound and Philadelphia Street westbound through York.