The Neorion Harbour (Greek: Λιμὴν τοῦ Νεωρίου or Λιμὴν τῶν Νεωρίων) was a harbour in the city of Constantinople, active from the foundation of the city in the 4th century until the late Ottoman period. It was the first port to be built in Constantinople after its re-foundation by Constantine the Great, and the second in the area after the Prosphorion, which was the port of ancient Byzantium.[1] [2]