OMPHALOS

[Greek] Omphalos (literally, "navel") is a sacred oval or hemispherical stone in Delphi. There it was situated in the center of the temple of Apollo (currently a museum). To the ancient Greeks this stone was the center, the 'navel', of the earth. According to legend, Zeus determined the spot by sending forth two eagles simultaneously to fly from the eastern and western ends of the earth, and they met at Delphi.