by Laura Lee

from LauraLee Website

YONAGUNI: The ancient underwater pyramid structure off the coast of Yonaguni-jima, Japan

Man-made, made by Nature, or did humankind finish what Nature started? These enigmatic, sunken stone structures off Okinawa, Japan, located 60 to 100 feet beneath the ocean surface, have the Japanese wondering if their homeland was once part of the lost continent of Mu.

Stone terraces, right angled block and walls, and stone circles encompassing hexagonal columns look intriguingly, if not conclusively, man made. A few more clues: an encircling road, what might be post holes supported long-gone wooden structures, what look like cut steps, and castles with similar architecture located nearby and still on land. (see photos; link at end of this article)

The two sites that are getting the most attention: near the city of Naha is Okinawa is what looks like a wall, with a coral encrusted right angled block. Another, just off the southern end of the tiny island of Yonaguni, the southernmost island of Japan, is an extensive site, with five irregular layers that look like ceremonial, terraced platforms. There are eight anomalous, underwater sites found to date.

Prof. Masaaki Kimura, a marine geologist with the University of the Ryukyus in Okinawa has spent several years studying all eight sties, especially Yonaguni, which was found 13 years ago, in 1985.

Kimura believes these are monuments made by man, left by an unknown civilization, perhaps from the Asian mainland, home of our oldest civilizations. He reasons that if the five layers on the Yonaguni site had been carved by nature, you would find debris from the erosion to have collected around the site, but no rock fragments have yet been found. He adds that there is what look like a road encircling the site as further indication it was used by man. He believes building this monument necessitated a high degree of technology, and some sort of machinery.

How to date these sites? A few possible scenarios have been suggested. The sites may have been submerged when sea levels rose at the end of the last Ice Age as the continental ice sheets melted. Or, as Japan sits on the Ring of Fire, tectonic activity might have caused subsidence of the land. Or perhaps a combination of subsidence and inundation from rising sea levels, or some catastrophic event, dropped it, intact and upright, into the ocean.


Teruaki Ishii, a professor of geology at Tokyo University, believes the site is partly man-made, partly natural, and suggests a date of 8,000 B.C., contemporary to the ancient civilizations of Mesopotamia and the Indus Valley. Others have suggested a date of 12,000 years.

The preliminary reports from the fist Americans to dive the sites:

Just back (May 1998) from diving two of the eight known sites are Mike Arbuthnot, an amateur underwater archeologist adventurer, and Boris Said, Executive Producer of the NBC documentary, "Mystery of the Sphinx." Both are experienced divers. Arbuthnot explored a three-mast schooner wrecked off Grand Cayman Island, and Said has been diving for 40 years.

It was treacherous terrain even for experienced divers. "The Yonaguni site is fairly near the shore, so there was heavy surge (the up and down motion of waves) as well as swift currents, and sharks," says Arbuthnot. "One the up side, the area has the third clearest water in the world, with visibility to 200 feet. And the corals were gorgeous."

"The two sites are very different, though both are at a comparable depth, 60 to 100 feet beneath the ocean’s surface. The Yonaguni site might be ceremonial platforms, and the Okinawa site seems similar to a castle wall, a conjecture that is supported by nearby castles on the island with a similar architectural style," says Arbuthnot.

Arbuthnot says that when he came up after the first dive, at Yonaguni, he found little to suggest that it was man made. It was only after diving the Okinawa site, and interviewing Prof. Kimura for two days, that he began to entertain the notion. The conversations with Prof. Kimura were all the more productive and in-depth, with the translating skills of Corina Tettinger, who speaks fluent Japanese.


"The case for the sites being artificial, or modified by man, requires supporting evidence," he says, and "we found very precise rectilinear stone features that seem to be indicative of either artificial tooling, or modifying the natural geology."


A particularly intriguing find: holes in the rock platforms. Could these be post holes to support a wooden structure? The terraces are massive, by human standards. But we can imagine naturally terraced platforms easily utilized for ceremonial purposes with the addition of wooden structures built atop them. You’d simply need to insert the supporting beams into the rock, by drilling a few holes.

"What we were able to observe was fascinating and warrants additional research," he says. "There is some false information on the sites out there. We want to bring clarity to the situation, and intend to mount a full-scale scientific expedition to do further investigation."

We'll report new developments on this project as they happen.

Geologist Robert Schoch and Egyptologist John Anthony West (both featured in the NBC documentary "The Mystery of the Sphinx") dove many months ago at Yonaguni, also without arriving at any conclusions, only more questions. Schoch focused on determining what geological forces might have been at work here.


While he notes that the strong currents might have cut the terraces out of the layered sediments, he has not ruled out human modification. Schoch says he very much wants to go back to dive again before arriving at any conclusions.

"I have not seen the other sites," he says, "and, not having previous diving experience, I spent much of my time underwater just staying alive."