In 1985, Kihachiro Aratake, a dive guide in Japan, was searching for a new site to view hammerheads. One day, he jumped into the water in western Japan, near Arakawa Point. Instead of sharks, he discovered something unusual: there, stretching over 300 feet into the distance, was a curious shape. Upon closer inspection, it appeared to be a man-made, terraced structure -- like gigantic steps -- featuring walls and perfectly round holes. Believing he had discovered a sunken city, Aratake announced his discovery, but news spread slowly. Later, in 1996, Professor Masaaki Kimura began to survey the structure. While Kimura maintains that the site is likely evidence for an advanced prehistoric civilization, others argue that the rock is the result of natural phenomena. Featuring tunnels, pillars, potential etchings in the rock, and a possible sundial, divers can visit Yonaguni, but due to the ripping current and the smoothness of the rock (which yields no hand-holds), it's tricky. To learn more about Yonaguni, check out:
- C. Hagland's assortment of short videos of Yonaguni. In addition to demonstrating the current, the clips show some of the very angular rock faces that look "too perfect" to be natural.
- Kimura's website, in which he maintains that the ruins are, indeed, man-made and somewhere between 6000 and 10,000 years old.
- The photo gallery provided by the Morien Institute, as well as a lengthy, interesting interview with Kimura.
- Travis' photos of Yonaguni.
- Wikitravel, which documents many of the topside rock formations near Yonaguni.
- Additional information, suggesting the discovery a road encircling Yonaguni, as well as more photos.
[Via Dive Happy]








1. The Underwater Pyramids look stunning on photos and film, and I'll be experiencing them first-hand in late December when I take a trip there and Ishigaki to do some diving. I've been in Okinawa 2 years now and it's crazy that I haven't dived the ruins yet.
Posted at 1:58AM on Oct 27th 2006 by Dave Webb