Long Island is a densely populated continental island east of Manhattan in southeastern New York state, constituting a significant share of the New York metropolitan area in both population and land area. The island extends from New York Harbor 118 miles eastward into the North Atlantic Ocean with a maximum north–south width of 23 miles. With a land ar…Long Island is a densely populated continental island east of Manhattan in southeastern New York state, constituting a significant share of the New York metropolitan area in both population and land area. The island extends from New York Harbor 118 miles eastward into the North Atlantic Ocean with a maximum north–south width of 23 miles. With a land area of 1,401 square miles, it is the largest island in the contiguous United States.