In the past, there was a small tower, which served as sea gate and called Egri Kule, in front of the Red Tower. The tower, its ruins still visible, was connected to Red Tower by a tunnel.
An exterior wall down to the sea at north of the Red Tower was collapsed and wharf was built in front. According to the researches, needs of Seljuk vessels such as food, water, soldiers and weapons were obtained from here. In the last period of Ottoman, a word of water supply above the tunnel was found in drawn the project of construction for harbor. A part of the tunnel was collapsed due to road crossing.
Connection from tunnel to ships was ensured by a portable bridge or ladder. Gallery part of collapsed tower, which provided a road to back of Red Tower and shipyard, still stands.