The Fortress of Rumelia (Turkish “Rumeli Hisarı”) is located near the narrowest point of the Bosphorus by the Göksu stream. It was built by Sultan Mehmet II in 1452 as a part of his successful siege of Constantinople, which he conquered in 1453. This fortress and the Fortress of Anatolia (Turkish “Anadolu Hisarı”) built by Beyazit I around 1390 cut off Constantinople from the Black Sea. It was originally known as Boğazkesen (“Cut-throat”).