YONAGUNI ISLAND

Yonaguni is the westernmost inhabited island of Japan, part of the Yaeyama Islands in Okinawa Prefecture.

It sits just over 100 kilometers from Taiwan and feels like the end of the map — remote, windswept, and filled with secrets.

With a population of under 2,000, the island is known for its rugged cliffs, wild horses, and a deeply rooted culture that blends Ryukyuan, Japanese, and Pacific Islander traditions. 

It’s also famous for being the only place in the world where Yonaguni horses roam freely — small, sturdy ponies once used in farming and now protected as a cultural treasure.

What truly put Yonaguni on the map for divers and explorers alike was the discovery of massive underwater structures in the 1980s by a local diver. 

These formations, at depths of 5 to 30 meters, feature sharp angles, flat surfaces, and enormous stone "steps" that resemble a sunken city.

Some geologists argue they are natural formations sculpted by tectonic activity and strong currents; others believe they are the remnants of a 10,000-year-old civilization lost to the sea.

This mystery draws not just divers, but also scientists, archaeologists, and adventurers chasing the blurred line between myth and reality.

Between late December and early March, Yonaguni becomes the stage for an incredible spectacle: schools of scalloped hammerhead sharks (Sphyrna lewini) cruising through the deep blue currents just offshore.

These aren’t just fleeting encounters — divers often report seeing 50, 100, even 300individuals in a single dive, moving together with an almost ghostlike synchronicity.

What makes this event even more special is how accessible it is compared to other hammerhead hotspots like Cocos Island or Galápagos. 

You don’t need to travel for days on a liveaboard. In Yonaguni, the sharks come right to the edge of the island’s drop-offs, just a 10- to 15-minute boat ride from shore.