Dildine Island is an island in the Delaware River in Warren County, New Jersey, near the county's border with Northampton County, Pennsylvania. The island is located at 40°51′28″N 075°03′31″W / 40.85778°N 75.05861°WCoordinates: 40°51′28″N 075°03′31″W / 40.85778°N 75.05861°W, approximately 4 miles (6 km) north of Belvidere, New Jersey.