Dodona, in northwestern Greece, was a prehistoric oracle devoted to the Greek god Zeus and to the Mother Goddess identified at other sites with Rhea or Gaia, but here called Dione. The shrine of Dodona was the oldest Hellenic oracle, according to the fifth-century historian Herodotus and in fact dates to pre-Hellenic times, perhaps as early as the second millennium BCE. Priests and priestesses in the sacred grove interpreted the rustling of the oak (or beech) leaves to determine the correct actions to be taken. Greek oracles are often misconstrued as having predicted the future.