Pennsylvania Route 148 is a 6.50-mile-long (10.46 km), north–south state highway located in Allegheny County, Pennsylvania. The southern terminus is at PA 48 in McKeesport. The northern terminus is at U.S. Route 30 in East McKeesport.

Allegheny County is a county in Pennsylvania, United States. As of the 2020 census, the population was 1,250,578, making it the state's second-most populous county, after Philadelphia County. Its county seat and most populous city is Pittsburgh, Pennsylvania's second most populous city. The county is part of the Greater Pittsburgh region of the state, and is the center of the Pittsburgh media market.