Located in the Sanctuary Preservation Area along with Sand Key and Eastern Dry Rocks, rock Key is a dive site that is also really great for snorkeling. The dive site is unique among wreck sites because the original ships that sunk in the area (one that was sailing from Barcelona, Spain in the 1800s and another one that is assumed to be a battleship) are barely distinguishable today as they is in many pieces. But a thorough exploration of the area around where the boats were will allow you to find a variety of interesting artifacts like brass fittings, many of the tiles the Spanish boat was transporting, and cannon balls and spikes from the battleship. No items are allowed to be removed from this area. The site is located one mile east of Sand Key. The site is in 20 feet of water and only allows for one diver at a time to explore the area.