Nan Madol

A city of basalt logs on a reef, built — islanders say — by two sorcerers and a dragon.

Nan Madol (Pohnpei, c. 1180-1600 CE): ~100 artificial islets built from basalt 'logs' weighing up to 50 tons, quarried across the island. Local tradition credits the sorcerer-brothers Olisihpa and Olosohpa with flying the stones. No ramps or rollers survive; the reef location adds difficulty. It anchors the Pacific megalith problem beside Easter Island.