Citadel: Quick Facts

Written and fact-checked by

The Information Architects of Encyclopaedia Britannica

Photos

Herāt, Afghanistan: ancient citadel

Sarzana: citadel

Aerial view of the ancient citadel of Erbil, a large fortified mound with historic buildings, surrounded by the modern cityscape of Erbil, Iraq.

The citadel mound in Irbil, Iraq, with large tan fortress walls and buildings atop a hill, and people sitting and walking in a plaza with benches and a blue umbrella in the foreground.

Besaçon, France

See All Images →

Topics

ciudadela pukío Acropolis fortification Castle Kremlin Martello tower alcazar 5 Famous Border Walls How was the Great Wall of China made?Parapet bastion battlement moat

Hagia Sophia. Istanbul, Turkey. Constantinople. Church of the Holy Wisdom. Church of the Divine Wisdom. Mosque.

Architecture: The Built World