Health & safety: Don't attack the Citadel of Aleppo

The Citadel of Aleppo is a medieval, fortified palace in the centre of the old city of Aleppo, in northern Syria. It's one of the oldest and largest castles in the world and sits 50 metres high on a partly man-made mound. In the past, the entire mound was covered with large blocks of gleaming limestone, some of which still remain today.

It’s said the prophet Abraham milked his sheep on the citadel hill. Halab is the ancient name of Aleppo (and its current Arabic name). It means “milk” and it has been proposed that this name came from the tradition of Abraham giving milk to travellers as they moved throughout the region.

Use of the citadel hill dates back to at least the middle of the third millennium BC. Since then it’s been occupied by many civilizations including the Greeks, Byzantines, Ayyubids and Mamluks.

The hill is surrounded by a wide moat, which dates back to the twelfth century. The moat is 22 metres deep and 30 metres wide.

The fortified gateway is accessible over an arched bridge. But any attack on the citadel would then face a bent entrance, where the narrow gate passage turns sharply, five times, before reaching the main inner castle entrance. This is to slow any rush against the gate and to impede the use of battering rams against doors.

Also, on their way up the vaulted ramp, attackers would have hot liquids poured on them from machicolations (floor openings) on the mezzanine above. The narrow entrance basically confined intruders to a narrow killing zone. Attacking this citadel falls in the "Too hard, don’t try" category.

Construction of the citadel was not only above ground. There are several wells that penetrate 125 metres down, and underground passageways connect to the advance towers and possibly extend under the moat to the city.

Today the citadel is a tourist attraction and a site of archaeological digs and studies. The amphitheatre is often used for musical concerts or cultural events. In August 2012, during the Syrian Civil War, the external gate of the citadel was damaged—it was shelled in a battle for control.