Yonaguni: a shark-diving guide found a 'sunken city' off Japan in 1986 and the f

Off the south tip of Yonaguni, westernmost Japan, near Taiwan. 1986, local dive operator Kihachiro Aratake is scouting hammerhead spots and finds this massive stepped formation underwater, ~25m tall, with flat terraces, sharp 90-degree edges, what look like steps, a 'road,' maybe a carved face. Now……