Potidaea (pŏtĬdē´ə), ancient city, NE Greece, at the narrowest point of the Pallene (now Kassándra) peninsula in Chalcidice (now Khalkidhikí). It was a Corinthian colony (c.600 BC) but joined the Athenian-dominated Delian League. Potidaea revolted (432) against Athens with Corinthian help, providing one of the incitements to the Peloponnesian War. Athens recaptured (430 or 429) the city. Philip II of Macedon took (356) Potidaea and may have destroyed it in the ensuing war. Rebuilt by Cassander, the city was named Cassandreia.