The Hydro Atlantic is a massive barge not far from Boca Raton Inlet. The ship was built for the U.S. Army Corps of Engineers in 1905 and sank in 1987. It's well known for thick blankets of coral and sponge, but also for a deck still crowded with equipment, cranes, and cables. Schools of fish form a circle around you as you swim through. There are large schools of jacks swimming around the wreck.