High Quality Content by WIKIPEDIA articles! The Safe Harbor Trestle also known as the Safe Harbor Bridge, Port Road Bridge and the Enola Low Grade Line (A S Railroad) Steel Trestle is a steel deck truss trestle that spans the Conestoga River at Safe Harbor, Pennsylvania near the Susquehanna River for the Port Road Branch and the former Columbia and Port Deposit Railroad along the Susquehanna River. It was built 1904 for the Atglen and Susquehanna Railroad.