Pennsylvania Route 512 is a 26.1-mile-long (42.0 km) state route in Northampton County in the Lehigh Valley region in eastern Pennsylvania. The southern terminus is at U.S. Route 22 north of Bethlehem in Hanover Township. The northern terminus is at PA 611 in Upper Mount Bethel Township. The route heads north from US 22 to Bath, where it intersects PA 248. From here, PA 512 continues northeast and intersects PA 946 in Moorestown before it reaches an interchange with the PA 33 freeway in Wind Gap. The route heads east through the northern Northampton County boroughs of Wind Gap, Pen Argyl, Bangor, and East Bangor, intersecting PA 191 in Bangor. It then continues east to PA 611.

Northampton County is a county in the Commonwealth of Pennsylvania, United States. As of the 2020 census, the population was 312,951. Its county seat is Easton. The county was formed in 1752 from parts of Bucks County. Its namesake was the county of Northamptonshire in England, and the county seat of Easton was named for Easton Neston, a country house in Northamptonshire. The county is part of the Southeast Pennsylvania region of the state.