Gölcük Naval Shipyard

Gölcük Naval Shipyard Gölcük Donanma Tersanesi
Part of Gölcük Naval Base
Gölcük, Kocaeli
Gölcük NSY Location of the Gölcük Naval Shipyard
Coordinates	40°43′23″N 29°48′11″E / 40.723°N 29.803°E / 40.723; 29.803Coordinates: 40°43′23″N 29°48′11″E / 40.723°N 29.803°E / 40.723; 29.803
Type	Military facility
Site information
Controlled by	Turkish Navy
Site history
In use	1926 - present
Garrison information
Past commanders	Associate Prof. Dr. Eng. Rear Admiral Nurhan Kahyaoğlu

Gölcük Naval Shipyard (Turkish: Gölcük Donanma Tersanesi) is a naval shipyard of the Turkish Navy within the Gölcük Naval Base on the east coast of the Sea of Marmara in Gölcük, Kocaeli. Established in 1926, the shipyard serves for the building and the maintenance of military vessels. A total of 3,221 personnel are employed at the shipyard stretching over an area of 255,526 m² (2,750,460 sq ft) with covered structures of 121,466 m² (1,307,450 sq ft).

To repair the war damages of the Turkish battlecruiser TCG Yavuz after World War I, a floating drydock, large enough to hold the big vessel, was needed. The site chosen was Gölcük on the southern shore of the Gulf of İzmit. With the construction of the floating drydock and the housing barracks by the German shipbuilding company Flender Werke, Gölcük Naval Shipyard was established in 1926.

The maintenance facilities were extended in 1942 with various other buildings, such as machine plant and foundry, stretching over a big swampland, a small lake and hazelnut orchard fields in Gölcük. The Convention on the Turkish straits, part of the Treaty of Lausanne signed in 1923, banned military facilities in the Turkish Straits. So, Turkish Navy's infrastructure, like shipyards and naval facilities, at the Golden Horn and İstinye in Istanbul were systematically relocated to Gölcük.