Key Largo

Key Largois acensus-designated placeinMonroe County,Florida, United States, located on the island ofKey Largoin the upperFlorida Keys. The name comes from theSpanishCayo Largo, or "long key". It is the first island of the Florida Keys and the originating point of theOverseas HighwaytoKey West. It is also the location of the first undersea park in the United States, established in 1963, and called theJohn Pennekamp Coral Reef State Park(located at Mile Marker 102). The park is primarily offshore and stretches three miles into the Atlantic Ocean and is 25 miles long. Adjacent to this is theFlorida Keys National Marine Sanctuarycovering 178 square nautical miles. Both areas were designed to protect marine life, including the extensive coral reefs in the area.