In Greek mythology, Atrax was the son of the river god Peneus and Bura. He was believed to have been the founder and eponym of Atrax or Atracia, a city in Thessaly. He had three daughters: Hippodamia (wife of Pirithous); Caenis, who transformed into a male, Caeneus; and Damasippe, who was married to Cassandrus of Thrace and fell in love with her stepson Hebrus (Cassandrus' son by his first wife Crotonice); as he rejected all her advances, she took revenge on him by falsely accusing him of seducing her; Cassandrus believed the accusations and tried to kill Hebrus, who threw himself into the river Rhombus, which was subsequently renamed Hebrus.