We all know that the ocean is a deep, and sometimes, frightening place. Massive creatures with large threatening teeth are just one of the things that have been found in the depths of the ocean, but there are even more terrifying things out there to be discovered. If you're already afraid of being in the ocean, then you should just stop reading right now because this list will surely give you nightmares.
In 1987, an odd structure was found off the coast of Japan. The structure has parallel faces, holes, sharp edges, and a triangular shaped pool. For obvious reasons, it was nicknamed “Japan’s Atlantis” and has been the center of debate for over 20 years. Some people believe that the structure is an underground city hidden from the public eye, while others believe that it’s simply a unique rock formation.