23. Yonaguni – The Underwater City?
in 1986, a diver was swimming around the Ryuku Islands in Japan, looking for a nice spot to observe hammerhead sharks. What he found instead was stunning, complex sandstone formations under the sea that are over 10,000 years old. These structures are now collectively called the ‘Yonaguni monument’.
Some marine geologists say that these are manmade ruins of a city that later sank underwater, and point to straight cut structures that look like pyramids, castles, and roads. Others, however, say that these are natural rock formations that look the way they do because of sea currents and erosion patterns of sandstone.