SEPTA Route 103 is a bus route operated by the Southeastern Pennsylvania Transportation Authority (SEPTA) on the outskirts of Philadelphia, Pennsylvania, United States. Route 103 runs between Ardmore and the 69th Street Transportation Center in Upper Darby. It began as a streetcar line in 1902, operated by the Ardmore and Llanerch Street Railway, then the Philadelphia Suburban Transportation Company (PSTC, doing business as Red Arrow Lines) until converted bus operation to December 1966. SEPTA acquired PSTC and assumed operations of the Red Arrow Lines in January 1970.