Pyrasus or Pyrasos was a town and polis (city-state) of Phthiotis in ancient Thessaly, mentioned by Homer along with Phylace and Iton as ruled by Protesilaus, in the Catalogue of Ships in the Iliad, and described by him as "Πύρρασον ἀνθεμόεντα, Δήμητρος τέμενος" Pyrasus was situated on the Pagasaean Gulf, at the distance of 20 stadia from Phthiotic Thebes, and possessed a good harbour. It had disappeared in the time of Strabo, the town having moved to a nearby site, called Demetrium or Demetrion (Δημήτριον), derived from the temple of Demeter, spoken of by Homer, and which Strabo describes as distant two stadia from Pyrasus.