Long Key is an island in the middle Florida Keys. Long Key was called Cayo Vivora (Rattlesnake Key) by early Spanish explorers, a reference to the shape of the island, which resembles a snake with its jaws open, rather than to its denizens. The city of Layton is located on Long Key. The 965-acre (3.9 km2) state park (3.9 km²) was dedicated October 1, 1969.U.S. 1 (or the Overseas Highway) crosses the key at approximately mile markers 65.5--71, between Fiesta Key and Conch Key.