It stands on the northeast corner of the walls, inside the Acropolis. The complex includes the byzantine castle with its ten towers and the prison facilities built inside and outside the castle. Although its original purpose was to protect the city’s inhabitants from invaders, during the Ottoman era it was converted into a prison (1890).
It was then that new buildings were added to the complex such as cell blocks, observation towers for the guards, isolation cells and administrative buildings. During WWII and the civil war that followed Yedi Kule became a notorious place, a place of tortures and death. Many prisoners were held here for their political beliefs and many criminals were cruelly executed. It was 1984 when an advocate managed to declare the prison complex inhuman and order its evacuation. It now serves as a museum, with visiting hours and tours taking place from various tourist organizations.