Adolf Fredriks kyrka ("The Church of Adolf Frederick") was built in 1768-1774, replacing a wooden chapel from 1674, which was dedicated to Saint Olof. René Descartes was first buried to the cemetery in 1650 (before his remains were moved to France). Inside the church is a memorial to the memory of Descartes installed by Gustav III. Other famous people buried in the church cemetery include Swedish Prime Minister Olof Palme who was assassinated only a block from the church, as well as Prime Minister Hjalmar Branting.
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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.