The 3st Ephorate of Byzantine Antiquitites is located in Chios and includes the perfectures of Chios.

The authority of the 3st Ephorate of Byzantine Antiquities refers to all matters concerning the discovery, safeguard and protection of Hellenic heritage, their exposition in museums, the conservation, reconstruction, study and publication of the monuments as well as the administrative duty to assure the observance of the legislative decrees concerning the antiquities.