Gölyazı settlement area is still inside the long ancient city walls which is about 800 meters long. The city walls were used both for defense and against lake floods. The walls, on which examples of traditional residential architecture can be seen, have gates and towers in some places. The most important of these is Simitçikale in the north. There is also a tower in the square. It is seen that the ruins of the outer castle surrounding the peninsula where the settlement located and the inner castle surrounding the island have been changed with spolia material over the centuries. Differing from place to place, Roman, Byzantine and Ottoman styles are intertwined.