RNZ reports the 98 man-made islets of Nan Madol on Pohnpei housed the tombs and ceremonial centre of the island's Saudeleur rulers hundreds of years ago.
The 83 hectare site, which received UNESCO World Heritage status in July, is made up of impressive stone monuments linked by a network of canals in a lagoon on the south-east side of Pohnpei.
One of the researchers involved in the study, archaeologist Mark McCoy, said advances in technology enabled the team to date the architectural stone and coral from the tomb of the first chief of the entire island.
