The Citadel is the largest British fortress built in North America. A unique location, it is an active military garrison, some of whose walls enclose 300 years of military history in Quebec City spanning the French, British and Canadian periods. Constructed between 1820 and 1850 based on the defence system designed by a French engineer named Vauban, La Citadelle of Quebec was built under the direction of Lieutenant-Colonel Elias Walker Durnford, a British army officer. La Citadelle is an active military garrison. First occupied by British troops and the Canadian artillery, since 1920 it has been the official residence of the Royal 22e Régiment, the only Francophone infantry regiment in the CF Regular Force. It is shaped like a polygon with four angles representing a star and covers 37 acres (2.3 km2).

La Citadelle comprises two buildings constructed under the French regime, the only real gate into Old Quebec City, the official residence of the Royal 22e Régiment, the Royal 22e Régiment Museum and the residence of the Governor General of Canada, among others. The Royal 22e Régiment Museum invites you to discover its guided tours, exhibits, activities, archives, collections and many other hidden treasures in La Citadelle!

Quebec City is the only North American who has retained all of its fortifications.