Long Key is an island in the middle Florida Keys, was once 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.
It runs between MM 65.5–71 and is boarded by Fiesta Key to the NE and Conch Key to the SW. It is the home of Long Key State Park, a favorite of campers and nature lovers, the camp sites are on the beach and the smallest incorporated town in the Florida Keys – Layton.