History is defined as the study of our past, particularly in human affairs. If these underwater photos from ocean floors all over the world are any indication, the human race has a lot more to learn.

A few years ago, I remember learning about some underwater pyramids off the coast of Okinawa, discovered in 1985 by a local tourism official who happened to be scuba diving in the area. Very few people know about these man-made structures on the sea floor despite the significance of their existence, both culturally and historically.

Japan is not the only country with an unknown history laying on the surrounding ocean floor. From neighboring China all the way to Jamaica, Greece, Israel, and Egypt, remnants of past civilizations lay asleep hundreds of meters under water. Only discovered around thirty years ago or less, these structures and statues hint at whole cities that flourished thousands of years ago and met an untimely end due to massive earthquakes and tsunamis, either literally sinking to the bottom of the ocean floor or being engulfed by rising sea waters. The only records of what actually happened to these ancient worlds are the underwater ruins themselves, leaving us only to wonder about what possibly could have happened to these flourishing cities and to realize that the same fate may await any one of us at some point in the distant future.

Ruins of Yonakuni, off the coast of Okinawa

Yonakuni pyramids

Atlit Yam, near Israel, discovered 1984

Pavlopetri, Greece, discovered in 1967

Heracleion, near Egypt, discovered in 2000

Port Royal, Jamaica, destroyed by tsunami in 1692

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Lion City, China's Atlantis, from above

Lion City