PA 441 crosses the Conewago Creek into Londonderry Township in Dauphin County and continues north between farmland and some woods to the east and the Norfolk Southern Royalton Branch and the Susquehanna River to the west. The route passes to the east of Three Mile Island, which is the location of the former Three Mile Island Nuclear Generating Station, the site of a partial nuclear meltdown in 1979. Past the former nuclear power plant, the road curves northwest and then north as it runs through wooded areas of homes with the river and railroad tracks to the west of the road. PA 441 crosses the Royalton Branch at-grade and enters the borough of Royalton, heading northwest through residential areas along Canal Street. The route becomes parallel to Amtrak's Keystone Corridor to the east and crosses the Swatara Creek into the borough of Middletown. Here, PA 441 follows Ann Street northwest before it turns north onto South Union Street, with PA 441 Truck continuing along Ann Street. The route runs past businesses and passes under Norfolk Southern's Royalton Branch and Amtrak's Keystone Corridor near Middletown Station. The road heads through the commercial downtown, crossing the Middletown and Hummelstown Railroad, which runs along Brown Street, at-grade before it crosses Emaus Street and continues into residential areas along North Union Street. PA 441 curves northwest and comes to an intersection with PA 230, at which point PA 441 Truck returns to the route. The route passes more homes and heads to the east of a cemetery, becoming the border between Lower Swatara Township to the west and the borough of Middletown to the east as it continues north and comes to a bridge over the Pennsylvania Turnpike (I-76).