New York City
Gateway National Recreation Area contains over 26,000 acres (10,521.83 ha) in total, most of it surrounded by New York City, including the Jamaica Bay Wildlife Refuge in Brooklyn and Queens, over 9,000 acres (36 km2) of salt marsh, islands, and water, including most of Jamaica Bay. Also in Queens, the park includes a significant portion of the western Rockaway Peninsula, most notably Jacob Riis Park and Fort Tilden. In Staten Island, the park includes Fort Wadsworth, with historic pre-Civil War era Battery Weed and Fort Tompkins, and Great Kills Park, with beaches, trails, and a marina.

Q: How large is the Gateway National recreation Area in hectares?
10,521.83