ancient Ionic city on the Mimas (now Kara Burun) peninsula in western Turkey. The original site of traditionally Cretan and later Ionian settlement is uncertain, but from the 4th century BC the city was located at modern Ildir, where traces of the wall circuit, theatre, and citadel are visible.

About 453 BC Erythrae, refusing to pay tribute, seceded from the Delian League. A garrison and a new government restored the union, but late in the Peloponnesian War (412 BC) it revolted again with Chios and Clazomenae. Freed from Persian rule by Alexander in 334, it supported the diadochos Antigonus I Monophthalmus. A free city in the Roman province of Asia, Erythrae was noted for its wine, goats, timber, and millstones, as well as its prophetic sibyls, Herophile and Athenais.