The USS Spiegel Grove was a Thomaston-class dock landing ship commissioned in 1956 and named after the Ohio estate of President Rutherford B. Hayes. After decommissioning in 1989, it was intentionally sunk as an artificial reef six miles off Key Largo in May 2002. The wreck is 510 feet long, making it one of the largest artificial reefs in the world.
The wreck is an advanced dive: the deck sits at around 60 feet, but the full hull descends to 130 feet, and the interior passages are complex and silty. It is not suitable for inexperienced divers and has claimed lives. For those with the training for it, the scale of the wreck — the massive hull plated with barnacles, the corridors of a warship now inhabited by goliath grouper and amberjack — is extraordinary. Dive operators throughout Key Largo offer guided trips to the site.