Hysiae or Hysiai (Ancient Greek: Ὑσιαί), also Hysia (Ὑσία), was a town of ancient Boeotia, in the Parasopia, at the northern foot of Mount Cithaeron, and on the high road from Thebes to Athens. It was said to have been a colony from Hyria, and to have been founded by Nycteus, father of Antiope.^[1] Herodotus says that both Hysiae and Oenoe were Attic demoi when they were taken by the Boeotians in 507 BCE.^[2] It probably, however, belonged to Plataea.^[3] Oenoe was recovered by the Athenians; but, as Mt. Cithaeron was the natural boundary between Attica and Boeotia, Hysiae continued to be a Boeotian town. Hysiae is mentioned in the operations which preceded the Battle of Plataea.^[4] Hysiae was in ruins in the time of Pausanias, who noticed there an unfinished temple of Apollo and a sacred well.^[5] Hysiae is mentioned also by Euripides^[6] and Thucydides.^[7]

Its site is located near modern Kriekouki in Erythres.^[8][9]

 This article incorporates text from a publication now in the public domain: Smith, William, ed. (1854–1857). "Hyle". Dictionary of Greek and Roman Geography. London: John Murray.