Amphion (/æmˈfaɪ.ɒn/ (Ancient Greek: Ἀμφίων, romanized: Amphíōn)) and Zethus (/ˈziːθəs/; Ζῆθος Zēthos) were, in ancient Greek mythology, the twin sons of Zeus (or Theobus)[2] by Antiope. They are important characters in one of the two founding myths of the city of Thebes, because they constructed the city's walls. Zethus or Amphion had a daughter who was called Neis (Νηίς), the Neitian gate at Thebes was believed to have derived its name from her.[3]