The Tersane Shipyard in Alanya is a historic maritime facility dating back to the Seljuk period. It was constructed under the rule of Sultan Alaeddin Keykubad I, with its completion in 1228. The shipyard represents one of the best-preserved examples of medieval naval architecture in the Mediterranean. The structure consists of five adjacent vaulted docks, each opening directly to the sea, which were used for the construction and repair of military and trade vessels. Its strategic location within the Alanya Castle complex provided a fortified and secure base for the Seljuk navy. For centuries, the shipyard played a crucial role in establishing Seljuk naval power in the region, controlling important trade routes along the southern coast of Anatolia. Today, the site functions as a museum and is open to the public, offering insight into the maritime history and shipbuilding techniques of the Seljuk era. It stands as a significant cultural heritage site, reflecting the historical importance of Alanya as a major naval and commercial port.