Cynus (Ancient Greek: Κῦνος, romanized: Kynos)[1] was the principal sea-port of the Opuntian Locrians, situated on a cape at the northern extremity of the Opuntian Gulf, opposite Aedepsus in Euboea, and at the distance of 60 stadia from Opus.[2][3] Livy gives an incorrect idea of the position of Cynus, when he describes it as situated on the coast, at the distance of a mile from Opus.[4] Cynus was an ancient town, being mentioned in the Homeric Catalogue of Ships in the Iliad.[5] It was reported to have been the residence of Deucalion and Pyrrha; the tomb of the latter was shown there.[2] Beside Livy and Homer, Cynus is mentioned by other ancient authors, including Strabo,[6] Pomponius Mela,[7] Pliny the Elder,[8] and Ptolemy.[9]
Colonists from Cynus founded Autocane in Aeolis, situated opposite the island of Lesbos.[10] It was one of the places that suffered the destruction caused by a tsunami that took place after an earthquake in 426 BCE.[11] In 207 BCE, during the First Macedonian War, Cynus, which appears defined as an emporium of Opus, was the place to which the fleet of Publius Sulpicius Galba Maximus retired after failing in its attack against Chalcis.[4]