Chaeronea, in ancient Greece, fortified town on Mt. Petrachus, guarding the entry into the northern plain of Boeotia. Controlled by the Boeotian city of Orchomenus (q.v.) in the 5th century bc, it was the scene of the battle in which Philip II of Macedon defeated Thebes and Athens (338 bc). The battle is commemorated by a statue of a large lion sitting on its haunches. In 86 bc Chaeronea was the scene of a victory of the Roman general Sulla over Mithradates VI of Pontus. The site is occupied by the modern town of Khairónia, Greece.