"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.
The only theism worthy of our respect believes in God not because of the way the world is made but in spite of that. The only theism that is no less profound than the Buddha's atheism is that represented in the Bible by Job and Jeremiah.