The truth behind Japan's mysterious 'Atlantis'
Beneath the coastal waters of the Japanese island of Yonaguni lies a series of mysterious rock formations. Since its discovery nearly 35 years ago, the strangely symmetrical shapes and structures of the 'Yonaguni Monument' have led to fierce debate over its true origins.
Could the odd shapes of this structure really have been carved by a lost Japanese civilisation many thousands of years ago, or is it just a stunning example of natural geology deep beneath the sea?
Video by Naotomo Umewaka