Sermylia (Ancient Greek: Σερμυλία),[1] or Sermyle (Σερμύλη),[2][3] was a town of Chalcidice, between Galepsus and Mecyberna, which gave its name to the Toronaic Gulf, which was also called Sermylicus Sinus (κόλπος Σερμυλικός - kolpos Sermylikos). Pseudo Scylax writes that it was a Greek city.[4] It was a member of the Delian League.[5]