Alligator Reef Lighthouse is considered one of the best diving and snorkeling locations in all the Florida Keys. Back in 1825, while on a mission against pirates of the coast of Islamorada, the USS Alligator sank in shallow water. To prevent the 86 foot long ship from being salvaged by the pirates, the crew blew her up and she landed in two pieces on the ocean floor. This was the beginning of the great coral reef that is now home to over 500 species of marine life.
The location is easily recognizable by the 136 foot lighthouse which pinpoints the location of the wreckage and the coral reef. The water depth of the coral reef ranges from 8 to 40 feet. This range of depth provides a great experience for all levels of divers. The Sanctuary Preservation Area covers .2 square miles and is clearly marked by mooring buoys and allows a preserved area for divers only.