4. The Yonaguni Monument: The 2000-year-old Japanese Underwater Ruins that May or May not be Man-made.
Exactly who was behind the construction of many mysterious structures is subject to speculation. However, some monuments are so unusual that some experts do not believe human hands built them at all. One such ancient monument is the Yonaguni Monument, which lies submerged off the southern coast of Yonaguni, one of the Ryukyu Islands of Japan. The monument consists of a collection of sandstone and mudstone carvings, columns, what appears to be a road, star-shaped platforms, and a massive stepped pyramid all stuck to the seabed.
Many people believe that the monument is a natural formation. The various structures seem to share parallel fractures and joints that experts believe were caused by seismic activity in the area. Their theory is that earthquakes fractured and displaced individual pieces of rock which were then eroded by the currents to produce the curiously carved stone ‘sculptures’ underwater today.” However, Masaaki Kimura, a professor at the University of Ryukyus is just one expert who believes the remains are human-made.
Professor Kimura bases his belief on the precise nature of the monuments. Some of the platforms bear circular and triangular holes that are too precise to be accidents of nature. Also, many of the individual slabs are cut at exact, sharp right angles rather than having the less precise, more rounded shape of a piece formed by erosion. Professor Mu has even gone so far as to date the structures to around 2000 years old. He also speculates that the Yonaguni Monument could be a ruin belonging to the lost civilization of Mu, now submerged beneath the waves of the Pacific.