Towering above the surrounding plains, stunning Kozan Castle stretches some 900m along a narrow ridge. It was built by Armenian King Leo I in the late 12th century. Inside the castle is a mess of ruined buildings, but continue up to the many-towered keep on the right. On the left is a massive tower, which once held the royal apartments. In all there are 44 towers and lookouts and the remains of a bedesten (covered market).
Along the 1km-long road to the castle are the ruins of an 18th-century church, locally called the manastır (monastery) demolished in the 1940s. From 1293 until 1921 this was the seat of the Katholikos (Patriarchate) of Sis, one of the two senior patriarchs of the Armenian Church.