Yonaguni: Mysterious Underwater Pyramid in Japan

By Ramzan Rafeek
Ramzan Rafeek
Ramzan Rafeek
October 7, 2011 Updated: September 29, 2015

Footage of Various Features at Yonaguni

Where can you find pyramids apart from Egypt? Maybe you’ve heard of the Incan pyramids in Peru, the pyramids of Nubia (Sudan), or the ruined pyramids of ancient Mesopotamia (Iraq) and Persia (Iran) known as ziggurats?

What you may not know is that the list was expanded in 1987, when dive tour operator Kihachiro Aratake discovered a massive stone structure in Japan, off the island Yonaguni, south of Okinawa.

This terraced pyramid appears to have been created using skilled craftsmanship and advanced technology yet belongs to prehistory. It did not attract much attention until experts and adventurers repeatedly dived at the site, photographing and unearthing this breathtaking structure and various features.

Dr. Masaaki Kimura, a marine geologist from the University of the Ryukyus, has been diving there for more than 18 years to measure and map the features of the Yonaguni Monument, as it has come to be called. The structure consists of a huge network of buildings, including castles, monuments, and a stadium, all connected by an elaborate system what seems to be roads and waterways.

It was most likely submerged during a massive earthquake and tsunami-like disaster. Japan is located in a region of great tectonic instability—the Pacific Ring of Fire. Severe earthquakes are very common in this area.

The world’s largest recorded tsunami struck Yonaguni in 1771 with an estimated height of more than 131 feet (40 meters). Such an event may have befallen the ancient civilization associated with this structure.

Kimura presented his research and a computer-generated model of the ruin site at a scientific conference in Japan in 2007.

According to Kimura, there are 10 submerged structures off Yonaguni, and a further five similar structures off the main island of Okinawa.

Massive ruins cover an area spanning more than 48,400 square feet (approx. 4,500 square meters). Kimura believes the ruins date back at least 5,000 years, based on the ages of stalactites found in underwater caves that he thinks sank with the city.

In fact, there are many underwater caves with stalactites in the waters off Okinawa. Stalactites and stalagmites can only form above water during an extremely slow process. Submerged caves with stalactites found around Okinawa indicate that much of the area was above water at one time.

Next Page: Another Sphinx Discovered at Yoganuni?