The search for Thomson’s “lost platform”, Ahu Rikiriki

Abstract

The paper presents an analysis of historical records and archival materials about Ahu Rikiriki, first mentioned by Thomson. The ahu was described as located on the southern cliffs of Rano Kau. In the 20th century, the site was searched for without success at the vertical cliffs below the Karikari, in the vicinity of ‘Ōrongo, suggesting that Ahu Rikiriki may have fallen into the sea in the late 19th or early 20th century. Other inaccessible places, such as the cliffs of Pōike were also mentioned as a possible location of Ahu Rikiriki. This study aimed to find the place at the Rano Kau caldera that would produce the best possible match with Thomson’s description of the ahu. The entire southern rim of Rano Kau was studied, both from the cliff top and from the sea. In one particular place, in the area formed by a large landslide, a patch of densely-packed stones was found in the middle of the cliffs, which may possibly represent remains of fill of a destroyed ahu. In the shallow surf under the site, one can see numerous ochre-colored boulders reminiscent of Rano Raraku tuff, standing out on the background of greyish stones that are common to the place. The dimensions of these ochre-colored boulders are within the ranges expected for moai.