Nan Madol is an archaeological site adjacent to the eastern shore of the island of Pohnpei, now part of the Madolenihmw district of Pohnpei state in the Federated States of Micronesia in the western Pacific Ocean. Nan Madol was the capital of the Saudeleur dynasty until about 1628.
The city, constructed in a lagoon, consists of a series of small artificial islands linked by a network of canals. The site core with its stone walls encloses an area approximately 1.5 km long by 0.5 km wide and it contains 92 artificial islets—stone and coral fill platforms—bordered by tidal canals.
https://en.wikipedia.org/wiki/Nan_Madol
The city, constructed in a lagoon, consists of a series of small artificial islands linked by a network of canals. The site core with its stone walls encloses an area approximately 1.5 km long by 0.5 km wide and it contains 92 artificial islets—stone and coral fill platforms—bordered by tidal canals.
https://en.wikipedia.org/wiki/Nan_Madol