The Citadel of Aleppo is one of the oldest and largest castles in the world. The castle sits atop a hill in the Ancient City of Aleppo, which was designated as a UNESCO World Heritage Site in 1986. Usage of the Citadel hill dates back to at least the 3000 BCE, but the majority of the current structure was probably built during the Ayuubid dynasty sometime during the 12th century.
During the early 2000s the Aga Khan Trust for Culture in collaboration with the Aleppo Archaeological Society performed extensive conservation work on the citadel. Unfortunately in recent years, the citadel has been severely damaged in the ongoing Syrian Civil War.
