Château du Guildo dates from the 11th century, when there was a fortified manor, probably made of wood. The stone castle was built in the 13th century in three phases. It was destroyed a century later and the new castle construction began in the late 1300s. Later it was restored as a living residence, but badly damaged in the late 1400s during the French-Breton War. The castle took part also to the Wars of Religion, when it was surrounded several times by Catholic League. This caused the final destruction Château du Guildo.
The Citadelle of Quebec is an active military installation and official residence of both the Canadian monarch and the Governor General of Canada. It is located atop Cap Diamant, adjoining the Plains of Abraham in Quebec City. The citadel is the oldest military building in Canada, and forms part of the fortifications of Quebec City, which is one of only two cities in North America still surrounded by fortifications, the other being Campeche, Mexico.
The first fortifications in Quebec were built by the Governor General of New France Louis de Buade, and completed just in time for the Battle of Quebec in 1690.
After the British conquest in the second half of the 18th century, the problem of Quebec City's defences grew more acute.