OPUS ('O7rois)  , in ancient Greece, the chief city of the Opuntian Locrians; the walls of the town may still be seen on a hill about 6 m . S.E. of the modern Atalante, and about i m. from the channel which separates the mainland from Euboea . It is mentioned in the Homeric catalogue among the towns of the Locrians, who were led by Ajax Oileus; and there were games called Aiantea and an altar at Opus in honour of Ajax . Opus was also the birthplace of Patroclus . Pindar's Ninth Olympian Ode is mainly devoted to the glory and traditions of Opus . Its founder was Opus the son of Zeus and Protogeneia, the daughter of an Elian Opus, or, according to another version, of Deucalion and Pyrrha, and the wife of Locros . The Locrians deserted the Greek side in the Persian Wars; they were among the allies of Sparta in the Peloponnesian War . In the struggle between Philip V. of Macedon and the Romans the town went over to the latter in 197 B.C., but the Acropolis held out for Philip until his defeat at Cynoscephalae (Livy xxxii . 32) . The town suffered from earthquakes, such as that which destroyed the neighbouring Atalante in 1894 .