U.S. Route 22 (US 22) is an east–west United States Numbered Highway that stretches from Cincinnati, Ohio, in the west, to Newark, New Jersey, in the east. In Pennsylvania, the route runs for 338.20 miles (544.28 km) between the West Virginia state line in Washington County, where it is a freeway through the western suburbs of Pittsburgh, and then runs east to Easton and the Pennsylvania–New Jersey state line in the Lehigh Valley region of eastern Pennsylvania.

Washington County is a county in the Commonwealth of Pennsylvania, United States. As of the 2020 census, the population was 209,349. Its county seat is Washington. The county is part of the Greater Pittsburgh region of the state.