Suez is a seaport city in north-eastern Egypt, located on the north coast of the Gulf of Suez. In the 7th century AD a town named Kolzum stood just north of the site of present-day Suez. Suez served as a source of drinking water for Kolzum. The Ayyubid sultan of Egypt, Saladin, fortified both Kolzum and Suez in to defend Egypt's eastern frontier from Crusader raids in the 12th century AD.