The Florida Keys are a coral cay archipelago located off the southern coast of Florida, forming the southernmost part of the continental United States. The city of Key West is the county seat of Monroe County. The county consists of a section on the mainland which is almost entirely in Everglades National Park, and the Keys islands from Key Largo to the Dry Tortugas. The islands lie along the Florida Straits, dividing the Atlantic Ocean to the east from the Gulf of Mexico to the northwest, and defining one edge of Florida Bay.