Ancient Mysteries · Ancient Alien Theory
The Yonaguni Monument
A sunken formation of terraces and right angles.
📍 Yonaguni, Japan
Ancient Mysteries · Ancient Alien Theory
A sunken formation of terraces and right angles.
📍 Yonaguni, Japan
Off the coast of Japan lies a drowned formation of flat terraces and sharp angles — natural rock, or a lost monument?
Off Yonaguni, the southernmost of Japan's Ryukyu Islands, divers in 1986 found a huge submerged formation of flat terraces, straight walls and sharp right angles, rising some 90 feet from the seabed. If it was shaped by human hands, it stood above water more than 10,000 years ago, at the end of the last Ice Age.
Geologists are split. Some see natural sandstone fracturing; others point to the steps, the right angles and what look like carved features as signs of a civilization far older than any we know. If it is man-made, it rewrites the timeline of monumental building — the kind of claim central to the lost-civilization and ancient-astronaut debate.
Reached by dive boat from Yonaguni Island in Okinawa Prefecture — an advanced-diver adventure to one of the ocean's great mysteries.
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