Les Catacombes in France

Established in 1810, the Catacombs are underground ossuaries full of skulls and bones of around six million people making it the largest grave in the world. One can enter the Catacombs through the western gate and has to descend a narrow spiral stair-well of 19 meters. After traversing a round 1.5 km long tunnel the visitors reach in front of the entry to the macabre place of the dead with human skulls and bones neatly arranged. The tunnel temperature is 14°C. Only 200 visitors are allowed at any time and the 45 minutes tour is unsuitable to people with heart and respiratory problem.
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