Petty Island (also Pettys Island; but typically spelled "Petty's Island" by area residents) is a 292-acre (1.18 km²) island located in the Delaware River, which forms the border between Pennsylvania and New Jersey in the United States. It is situated between the cities of Philadelphia, Pennsylvania and Camden, New Jersey, and can be seen from both the Benjamin Franklin Bridge and the Betsy Ross Bridge. It is the fourth-largest island in the Delaware River's path.