Anadolu Hisarı (also known as Güzelce Hisarı) is located in the Anadoluhisarı district of Istanbul, where the Göksu Creek flows into the Bosphorus.
The Anatolian fortress was built by Yıldırım Beyazıt in 7.000 on an area of 660 square meters, in the area of 1395 meters from the narrowest point of the Bosphorus. Genoese were united with Byzantium and established colonies in the Black Sea (Kefe, Sinop and Amasra). For this reason, the Bosphorus crossing was vital for the Genoese. The same was true for the Ottomans. Rumeli Fortress, located on the opposite beach, on the European side of Istanbul, was built between 1451 and 1452. It was built by Mehmed in order to control the passage of the ships of these foreign countries. While Fatih Sultan Mehmed built the Rumeli Fortress, he added external walls to this castle.
Anadolu Fortress consists of the inner and outer fortresses and the walls of these fortresses. The inner castle is a rectangular four-storey tower. When it was first built, the tower was entered through a suspension bridge extending to the inner fortress walls, since there was no entrance door. The upper floors were also reached by wooden stairs inside.
The inner fortress walls connect the northeast and northwest corners of the outer fortress. These walls are three meters thick. There are many arches and three towers built to protect the walls on the outer fortress walls, which join with the inner walls. The walls of the main castle are 65 meters in east-west direction; It extends for 80 meters in the north-south direction. The thickness of the walls is 2.5 meters. There are culverts in the outer walls where balls are placed. Block stones filled with mortar were used in the main fortress and inner walls of Anadolu Hisarı.
Anadolu Hisarı has lost its military importance after the conquest of Istanbul, and its environment has become a residential area over time. The road passes through the middle of Anadolu Fortress, some parts of which are ruined.