"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.
There's no one I trust in show business more than Sabrina Wind. She's my eyes and ears when I can't be there. She weighs in on everything, from scripts to sets to advertising.