The Citadel of Aleppo is considered one of the old...

The Citadel of Aleppo is considered one of the oldest and largest castles in the world, the use of the hill on which the castle is located dates back to the third millennium BC, when it was later occupied by many civilizations, including the Greeks, Byzantines, Mamluks and Ayyubids, while it appears that most of the current building dates back to the Ayyubid period.