Quelle est l'histoire derrière les catacombes à Paris?

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So it went to the tunnels, moving bones from the cemeteries five stories underground into Paris' former quarries. Cemeteries began to be emptied in 1786, beginning with Les Innocents. It took the city 12 years to move all the bones-from bodies numbering between 6 and 7 million-into the catacombs.