Some areas of the Citadelle are off-limits, as it is still the headquarters of the Royal 22nd Regiment. Occupying the old gunpowder magazine, the museum charts 100 years of the history of this infantry regiment. Erected between 1819 and 1831, this massive fortress, set on 16ha/40 acres, is typical of star-shaped fortifications. A guided tour will reveal the King's Bastion, the redoubt of Cap Diamant and the Governor General's residence.