Known as the Rumeli Fortress

One of the most beautiful masterpieces of military architecture in the world, also known as the Fortress of Europe, was built in just four months by Sultan Mehmed the Conqueror during the conquest of Istanbul (1452). It was built by Sultan Mehmed II of the Ottoman Empire in 1452, before the conquest of Constantinople. On the Asian side opposite it is another Ottoman fortress, the Anatolian Fortress, built from 1393 to 1394 by Sultan Bayezid I. The Rumeli Fortress has a small tower, three main towers, and 13 small watchtowers on the walls connecting the main towers. The three main towers are named after the three Pashas who supervised the construction. The Sultan also personally inspected the project on site. The main tower on the north is cylindrical, 9 stories high, 28 meters, 23.3 meters in diameter, and 7 meters thick. Today, this tower is called the "Fatih (Conqueror) Tower", named after Sultan Mehmed II. The Halil Pasha Tower, a dodecagon, is located in the middle, also 9 stories high, 22 meters high, 23.3 meters in diameter, and 6.5 meters thick. The main tower on the south, the Zaganos Pasha Tower, has only 8 stories, is cylindrical, 21 meters high, 26.7 meters in diameter, and 5.7 meters thick. The interior space of each tower is separated by wooden floors. The total area of the fortress is 31,250 square meters.