Nan Madol: The Stone City That Opened Only by Water

More than one hundred artificial islets sit in the lagoon off Pohnpei in the Federated States of Micronesia. Builders stacked long basalt columns into walls, laid foundations on coral, and linked the islets with tidal canals. Between about 1200 and 1500 CE, Nan Madol rose as the ceremonial and political centre of the Saudeleur dynasty, and large parts of the city could be reached only by boat.

UNESCO describes a complex of palaces, temples, tombs, and stone houses built by a highly organised island society. The U.S. National Park Service records that for roughly five hundred years Nan Madol served government, markets, defence, and ceremony at once. The whole city stands on a coral reef, and not one strip of land connects its islets. When the tide rises, the water becomes the only entrance, and a full control system starts right there. The water level changes from day to day, so the people in charge decide which gate opens and which stays shut, a toll collected on the surface of the water that nobody can slip past. Anyone who wants to meet the ruler, reach the royal tombs, or attend a ceremony must take the right channel, land on the right islet, at the right time. Whoever holds the canoe routes holds the food stores, the road to the dead, and every piece of information the court owns.