shallow inlet of the Atlantic Ocean covering about 20 square miles (50 square km) on the southwestern shore of Long Island, southeastern New York, U.S. Part of the Port of New York, the bay is sheltered on the south by Rockaway Peninsula and is traversed by the Cross Bay Boulevard. Dotted with marshy islands, Jamaica Bay connects with the ocean to the southwest by way of Rockaway Inlet, which is bridged. Near the entrance channel is Coney Island. On the Brooklyn shore is Floyd Bennett Field, a former U.S. naval air station that is now part of the Gateway National Recreation Area; on the northeastern shore, at Idlewild, is the John F. Kennedy International Airport.