The first major collapse occurred in December 1774, when an unstable tunnel crumbled, swallowing houses and people along what is now the Avenue Denfert-Rochereau.

坍塌事件最先发生在1774年的十二月，一条隧道突然坍塌使周围的建筑和一些居民陷入地下，事故发生地就是现在的当费.罗什罗大街。

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For those who want to find out, but are not willing to take the risk of going in unsupervised, there is a legal, tourist-friendly public entrance to the catacombs off Place Denfert-Rochereau.

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