Interstate 180 (I-180) is a spur highway in Pennsylvania that connects Williamsport to I-80 near Milton. The length of the highway is 28.84 miles (46.41 km). It was also the designation of present-day I-176 between Morgantown and Reading, when the Pennsylvania Turnpike carried the "I-80S" designation in the 1960s. It is signed as an east–west route for its entire length, even though half of the route runs north–south.

Williamsport is a city in and the county seat of Lycoming County, Pennsylvania, United States. As of the 2020 census, it had a population of 27,754. It is the principal city of the Williamsport Metropolitan Statistical Area, which has a population of about 114,000. Williamsport is the larger principal city of the Williamsport-Lock Haven Combined Statistical Area, which includes Lycoming and Clinton counties.