Devil's Eye Caverns

Devil's Eye Caverns was a shipwreck site located in the Cruz region of the Caribbean. A set of sprawling underwater caves primarily inhabited by jellyfish and sea urchins, they were explored by the pirate Edward Kenway during the early 18th century.

While navigating the cave system via strong underwater currents, Edward managed to locate and loot several sunken treasure chests, gaining money and an upgrade plan for his own vessel, the Jackdaw.

Trivia

 * Devil's Eye Caverns was the only underwater location where Edward was able to briefly explore on foot, due to a small part of the cave system being above sea level.

Reference

 * Assassin's Creed IV: Black Flag