The citadel is located on the heights of Verdun and covers part of the site occupied by the old Benedictine Saint-Vanne Abbey, founded in the 10th century. It was a leading institution during the Romanesque period, and saw major transformation from the late Middle Ages.
After the town was annexed by Henry II of France in 1552, a citadel was built on the site. Progressively, the King’s engineers transformed the religious buildings into military fortifications, and at the end of the 17th century, Vauban reinforced this strategic area of the town. Nevertheless, the monastery continued to operate, the monks living side by side with the troops. During the French Revolution, the abbey was converted into a barracks. It was gradually dismantled through until 1870, leaving just one tower which can still be seen. This was used as an observation and wireless telegraphy post during the First World War. The citadel was extensively remodelled during the 19th century. The engineers dug a vast network of underground tunnels to shelter troops, ammunition depots and command posts. This work, which continued into the early 20th century, led to the development of the underground citadel, an actual subterranean military town.
The citadel played a major role during the Battle of Verdun in 1916, as a logistics centre, a resting place and a shelter for the general staff. The ceremony to choose the Unknown Soldier, who was to be laid to rest under the Arc de Triomphe in Paris, took place in the citadel on 10 November 1920. It has been listed as a historic monument since 1929.