Harput Castle, also known as Milk Castle (Turkish: Harput Kalesi, Süt Kalesi), is a castle located in the historical Harput neighborhood within the borders of the current Elazığ Province, Turkey.[1][2] It was built by the Urartians on a rectangular plan.[3] The castle consists of two parts, internal and external. According to legend, a scarcity of water and abundance of milk during its construction meant that milk was added to the castle's mortar, leading to it being sometimes called "Milk Castle".[4][5]