 The road crosses a Union County Industrial Railroad line and continues into the commercial downtown of Lewisburg.The route passes through the downtown before it runs through residential areas and comes to a bridge over the West Branch Susquehanna River.Upon crossing the West Branch Susquehanna River, PA 45 enters West Chillisquaque Township in Northumberland County and becomes an unnamed road, immediately coming to an intersection with PA 405 in the community of East Lewisburg.