Easter Island

Platforms served as social and religious centres, and also as boundary markers. A few platforms seem to have been built to contain burials, but this does not seem to have been the original function of the image platforms. No early skeletons have been discovered, whereas elaborate cremation pits have been found behind the central platform at many complexes, in contrast to the rest of central and eastern Polynesia, where cremation was not practised. At a later stage, bodies were interred in stone-lined tombs in the platforms and ramps. After the moai had been toppled, bodies were placed around the fallen moai or on other parts of ramps and then covered with stones. Semi-pyramidal platforms were the last type of ahu to be built: they were usually superimposed on the earlier, statue-bearing platforms, and seem to have been designed purely for burial purposes. Less than 75 are known, compared with more than 125 image platforms.

Some platforms seem to have been built in a single episode, but most image platforms show evidence of more than one construction phase, and some as many as eight. Based on radiocarbon dating, the earliest structure, at Tahai, is dated at 690 AD, though some archaeologists regard the association of the dated material with the structure as extremely doubtful.1 Platform building is generally believed to have become an obsession by 1200, and to have lasted until well into the 16th century.