"Ahu" are stone platforms on which many moai sit. There are 313 known ahu and 125 of these carry moai. The biggest, Ahu Tongariki is 220 m (720 ft), and had the most (15) and tallest moai.
No man is so foolish but he may sometimes give another good counsel, and no man so wise that he may not easily err if he takes no other counsel than his own. He that is taught only by himself has a fool for a master.