This island, similar to the others, is a raised atoll surrounded by densely forested makatea.
It is not more than 20 m asl, therefore, the caves generally end in a fresh water or slightly saline pool, and often they continue below the water table.
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Other interesting caves are to be found in the northern part of the island. Vai Ou is a narrow shaft, which ends in a water filled hole. Vai Moraro (Crawling Cave) comprises of a series of small chambers with slightly saline pools at the bottom. The main cave can be accessed from the entrance through a very narrow crawl. Vai Tunamea is a deep hole with a pool at the bottom.
Text from George Szentes (2004): Caves of the Cook Islands, The British Caver Vol. 127 Spring 2005, pp 1-12, 13 color pictures, 1 bw picture, 1 map. With kind permission of the author.