Snow Monkeys | Guide to Yudanaka Shibu Onsen area. Underwater Pyramids: Mysterious Ancient Man-Made Structures Found Underwater (Video) | Higher Learning. A structure known as the Yonaguni monument or “Japan’s Atlantis” is located underwater in the Yaeyama Islands off the westernmost point of Japan. The tiny island of Yonaguni is difficult to reach but has remained popular due to the discovery of the Yonaguni monument in 1986. According to CNN Exactly how the underwater pyramid structure, known as the Yonaguni monument, was formed is still under debate. Some claim the ruins to be evidence of a long lost city, while others are convinced it is a geological phenomenon.
There are even a few who believe the site to be the work of architecturally-ambitious aliens. Whatever its origin, it’s an impressive site. Estimated to be between 5,000 and 8,000 years old, the stepped structures — with smooth platform steps and right angles — appear as though they were carved out of the rock.” Related articles Like this: Like Loading... Related Japan's Newest Island Just Got A Lot Bigger In "archipelago"