The Yonaguni Jima Monument
In 1987, archaeologists discovered a 50-meter-long by 20-meter-wide sunken city that’s been dubbed Japan’s Atlantis. It quickly attracted many divers curious to study the site in more detail. At first glance, the site looks like a stacked-pyramid that some researchers believe to be over 10,000 years old. It’s located at a depth of 16 to 131 feet below the coast of the Ryukyu Islands.