Oea or Oia () or Oee or Oie (Οἴη) or Oe (Ὄη or Ὀή) was a deme of ancient Athens.
The location of Oea has been a matter of debate, with some situating it above the Pythium, to the west of Mount Aegaleos, to the north of the pass of Poecilum,Sophocles, Oed. Col. 1061, Οἰάτιδος ἐκ νόμου, with the Schol. and recent work putting the site northeast of Aspropyrgos.
In the Boule of 500, Oea held six seats, and the deme seems to have maintained this rough scale into the Roman period.
Notable citizens Damonides, Athenian musicologist and advisor to Pericles Eratosthenes, famous adulterer in Lysias' first speech Lamachus, Athenian general, son of Xenophanes Tydeus, Athenian general, son of Lamachus
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