Kontoskalion

The Kontoskalion (Greek: Κοντοσκάλιον), also known as Harbour of Julian (Latin: Portus Iulianus, Greek: Λιμὴν τοῦ Ἰουλιανοῦ), Portus Novus ("New Port"), or Harbour of Sophia (Greek: Λιμὴν τῆς Σοφίας or Λιμὴν τῶν Σοφιῶν), and in Ottoman times as Kadırga Limanı ("Harbour of the Galleys") was a harbour in the city of Constantinople, active from the 6th century until the early Ottoman period. In the literature it has been known under several names, and the sources about it are often contradictory.

The harbour lay in an inlet – still recognizable today in the flat landscape profile – of the Marmara Sea, in the third region of the city, at the southwest end of the valley of the Hippodrome. The area of the harbour complex covers part of today's Mahalleler of Kadırga Limanı and Kumkapi in the Fatih district (the walled city) of Istanbul.

Already during the reign of Constantine the Great (r. 306–337) the site of the later harbour was used as a landing stage. In 362, during his short stay in the capital, Emperor Julian (r. 361-363) built on the Propontis shore a harbour named Portus Novus ("New Port") or Portus Iulianus (Greek: Λιμὴν τοῦ Ἰουλιανοῦ): at the same time he erected in front of it a crescent-shaped building named Sigma or Porticus Semirotunda. This decision was taken despite the many problems which affected the location: each port along the Marmara shore was undefended against the fierce storms caused by the intermittent southwest wind, the Lodos; these brought much sand into the basin, making necessary a periodic and expensive dredging; moreover, the heavy rains provoked erosion from the hills which caused silting too. On the other hand, the building of a harbour on the south shore was necessary to supply the western and southern regions of the city, too far from the Golden Horn.

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Wikipedia