http://agathe.gr/guide/aiakeion.html
Aiakeion Immediately to the east are the poor remains of a large square enclosure, open to the sky and measuring about 30 meters on a side. Built in the early 5th century, at the command of the oracle ... Built in the early 5th century, at the command of the oracle of Apollo at Delphi, it was dedicated to Aiakos, a hero of the island of Aegina. By the early 4th century it was used for the storage and distribution of substantial amounts of grain.