This Byzantine hilltop fortress, with its moat, two dozen towers and vaulted underground chambers, was once Silifke's command centre. It was originally built by the Byzantines during the 7th-century Arab raids, though the present structure dates from 500 years later. The walls are its most impressive (and at present only visible) feature, as the interior is still undergoing excavation. At the time of writing, archaeological and restoration work meant the entire castle was off limits except for the viewing terrace.