Spiegel Grove wreck dive

At 510 feet long, the retired Navy landing ship Spiegel Grove was the largest vessel ever sunk on purpose to make a dive reef when it went down six miles off Key Largo in 2002. It sank early and upside down, was rolled onto its side weeks later, and Hurricane Dennis finished the job in 2005 by standing it upright on the sand in 130 feet of water.

The top deck is around 60 feet down, and on most days the far end of the ship fades out of sight. Groupers and big schools of fish live on it and coral is spreading over the hull. Dive shops want advanced open water certification or a logbook that shows good air management. Going inside is for divers with overhead-environment training only, and never below about 90 feet or the main deck: silt inside can drop visibility to nothing, and several divers have died in the wreck. Dive boats from the Key Largo marinas tie off on mooring buoys over it.