- Western Terminus:
- Pottsville Pike (PA 61) in Leesport
- Eastern Terminus:
- New Jersey-Pennsylvania state line
- 60.08 miles
- Berks, Montgomery, Philadelphia
PA 73 is a diagonal route through Philadelphia and its suburbs and exurbs. It begins at Pottsville Pike (PA 61) in Leesport and runs southeast toward Philadelphia. It crosses the city on Cottman Avenue and then follows State Road and New State Road to the Tacony-Palmyra Bridge, which crosses the Delaware River to New Jersey. It becomes NJ 73 at the state line.