Strange Places: The Yonaguni Monument

The sea is the last significant unexplored territory on Earth. Mysteries and legends surrounding the planet’s vast oceans have developed over millennia of human interaction with these unforgiving bodies of water. The danger and unknown have given rise to tales of strange creatures, ghost ships and even sunken cities. While the most famous of these lost civilisation myths is undoubtedly Atlantis, it has a modern rival. Located off the coast of Yonaguni, the southernmost of the Japanese Ryukyu Islands, the Yonaguni Monument is believed by some to be a sunken city.

It was in 1986 that Kihachiro Aratake, a director at the Yonaguni-Cho Tourism Association, was diving in the sea off Yonaguni while looking to observe the noted local population of Hammerhead Sharks. Described as “a fierce-looking, bearded man”, Aratake was a professional diver and not likely taken to flights of fancy. However, while under the water, he made a startling discovery — rock formations.

Describing the find as “breathtaking”, Aratake was in no doubt that what he was seeing could not be natural. What he saw were huge geometric terraces, the stone appearing to have broad and flat horizontal surfaces. Sheer vertical stone risers gave the appearance of a ruined building or monument.

Word quickly spread of the find and a group of scientists directed by Professor Masaaki Kimura of the University of the Ryūkyūs soon visited to ascertain the veracity of what Aratake believed he had discovered. Kimura was a marine seismologist with a particular interest in the legends surrounding lost civilisations. He was the author of a book that argued for the existence of the legendary city of Lemuria. Like Atlantis, Lemuria is said to have sunk beneath the ocean in antiquity. While many would put such belief down to pseudohistory, Kimura’s credentials add weight to his theories. He is a doctor of marine geology and has worked for the University of Tokyo’s Ocean Research Institute, the Geological Survey of Japan, the Agency of Industrial Science and Technology of the Ministry of International Trade and Industry of Japan, and Columbia University’s Lamont-Doherty Earth Observatory. He theories cannot be dismissed lightly.

Through the 1990s, Kimura worked extensively at what became known as the Yonaguni Monument. He dived with his students and compiled a wealth of information on the location. During these dives, the professor found several other sites of interest in the area and came to firmly believe that they were manmade or, at least, a natural formation that had been enhanced by man, matching Kihachiro Aratake’s initial feelings.

“I think it’s very difficult to explain away their origin as being purely natural, because of the vast amount of evidence of man’s influence on the structures. The characters and animal monuments in the water, which I have been able to partially recover in my laboratory, suggest the culture comes from the Asian continent. One example I have described as an underwater sphinx resembles a Chinese or ancient Okinawan king.”

Masaaki Kimura, as quoted by National Geographic

In 2007, he submitted a report to the 21st Pacific Science Congress that stated he believed the workings to be between 2,000 and 3,000 years old and identified several structures including a pyramid, castles and roads. He added that sea levels at that time would have been much lower, putting the submergence down to tectonic activity. The professor was insistent that the formation was not natural, claiming to have seen clear quarry marks, stone tools and a stone tablet carved with ancient lettering.

“The largest structure looks like a complicated, monolithic, stepped pyramid that rises from a depth of 25 meters [82 feet]”

Masaaki Kimura, as quoted by National Geographic

However, the findings of Kimura are heavily disputed and mostly rejected by both scientists and historians alike, with Robert Schoch, a geologist at the University of Boston, being one of the leading names to oppose the suggestions. Like Kimura, Schoch has dived at Yonaguni many times, yet believes the Yonaguni Monument is entirely natural. He points out that the stones are bedrock, not separate blocks as would be expected in structures. He adds that, as the rock is sedimentary, it has horizontal layers that break along parallel lines when it erodes, creating the illusion of manmade angles and cutting. The tectonic activity highlighted by Kimura would also result in horizontal splitting. Equally, Schoch believes the “quarry marks” are also entirely natural.

“[The sandstones] contain numerous well-defined, parallel bedding planes along which the layers easily separate. The rocks of this group are also criss-crossed by numerous sets of parallel, vertically oriented joints in the rock. These joints are natural, parallel fractures by which the rectangular formations seen in the area likely formed. Yonaguni lies in an earthquake-prone region; such earthquakes tend to fracture the rocks in a regular manner.”

Robert Schoch, University of Boston

Other researchers such as Richard Pearson, a specialist in the archaeology of East Asia, believe it unlikely that Kimura’s hypothesis surrounding tectonic activity is correct. Pearson also highlights evidence from Yonaguni Island that suggests local communities were small. These findings came from encampments and included large fireplaces, stone tools and thick brown pottery, dating to 2000 to 2500 BC. None of the results indicates a civilisation capable of building such proposed large stone monuments.

Despite the criticism, Robert Schoch offers a compromise solution, suggesting that the communities present on Yonaguni Island may have seen certain rock formations as necessary to their culture and modified them close to what was then the shoreline, making them appear artificial. Despite the olive branch, he remains convinced that the structure is more than likely entirely natural.

“You get a regular blocky structure quite naturally.”

Robert Schoch, New Scientist

Professor Kimura has also come under criticism for repeatedly revising his beliefs regarding the structure, having first proposed that what had been discovered could be 6,000 years old. His identification of the “ruins” with the lost city of Yamatai and the legendary continent of Mu has also been derided.

Mu is a hypothesised lost continent that has been identified as both an alternative term for Atlantis and Lemuria. The name was first introduced by the British archaeologist Augustus Le Plongeon whose writings have long been debunked in archaeological circles. After working at the Maya ruins in Yucatán, Le Plongeon claimed to have translated sacred works to discover the story of “Mu”, believing this was Atlantis.

“In our journey westward across the Atlantic we shall pass in sight of that spot where once existed the pride and life of the ocean, the Land of Mu, which, at the epoch that we have been considering, had not yet been visited by the wrath of Human, that lord of volcanic fires to whose fury it afterward fell a victim. The description of that land given to Solon by Sonchis, priest at Sais; its destruction by earthquakes, and submergence, recorded by Plato in his Timaeus, have been told and retold so many times that it is useless to encumber these pages with a repetition of it.”

Augustus Le Plongeon, Queen Móo & The Egyptian Sphinx

The concept was later linked to Lemuria by the British occult writer James Churchward who claimed that he had seen Maya tablets in India that identified “Mu” as the fabled lost continent that supposedly sank in the Indian Ocean. Proposed by zoologist Philip Sclater, like Atlantis, Lemuria has long been debunked. However, Lemuria is somewhat different from Atlantis as it has no mythological basis, instead originating as a scientific theory to explain why lemurs have habitats in Africa, India and on the island of Madagascar. The idea fell out of favour in the 1960s when continental drift became proven scientific fact. Despite this, believers in ancient civilisations, technology and even ancient aliens, have all kept the theory alive, moving far away from the original scientific intent of Sclater.

Yamatai, meanwhile, is one of the most debated topics in Japanese historiography and full of controversy and fierce debate at every turn. While a real place, the domain of Priest-Queen Himiko, it’s location is lost to history and consensus suggests its location is either northern Kyūshū or Yamato Province of central Honshū.

While the claims of Professor Masaaki Kimura appeal to our sense of wonder and attraction to the mysterious, the link to theories such as “Mu” do him no favours amongst the scientific community and sceptics alike. Neither the Japanese government’s Agency for Cultural Affairs nor the government of Okinawa Prefecture recognise the Yonaguni Monument as points of cultural interest. Yet, Kimura is far from alone in his belief, even amongst scientists, with Toru Ouchi, an associate professor of seismology at Kobe University, supporting Kimura’s hypothesis.

“I’ve dived there as well and touched the pyramid. What Professor Kimura says is not exaggerated at all. It’s easy to tell that those relics were not caused by earthquakes.”

Toru Ouchi, as quoted by National Geographic

The district of Yonaguni officially owns the mysterious formations, and both tourists and researchers alike can freely dive at the site. Whether the structures are genuinely manmade or merely the work of the planet’s extraordinary natural processes, they remain a breathtaking sight. Should readers ever find themselves seeking adventure in Japan, perhaps Professor Kimura’s experience offers advice for researchers and the public that they may wish to visit and judge for themselves.

“The best way to get a definitive answer about their origins is to keep going back and collecting more evidence. If I’d not had a chance to see these structures for myself, I might be sceptical as well.”

Masaaki Kimura, as quoted by National Geographic

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