The Catacombs of Paris are a re use of the quarries of the city:
All quarries, no indeed it is necessary to differentiate
the quarries of gypsum serving mainly for giving with the platre which are located north of the capital. Those of the mount montmartre and of the park montsouris the most knowing are.
Quarries of limestone for use as stone for construction which were dug in tunnel.Those served for building the city which knew a concentric growth around the islands of ancient lutéce. That’s how a lot of the city finds itself underground by quarries stretching in periphery of the city.
These underground spaces were consolidated by an official organism IGC and used when the Pari sian graveyards began overflowing considering the population growth of the capital. Finaly the problem of health was gravely implicated.
The solution in this fact was to exhume bones and to transfer them in the ancient quarries left around
Paris. The choice was carried on those located near the « place Denfert rochereau. XIV arrondissement ». That’s how nightly from 1786 till 1814 the bonnes of differents graveyards Parisian were emptied and stocked by place of origin in the ancient galleries.
The catacombs of Paris had been born. Those ci are visitables, it is call « ossuaire municipal de paris ».
Remain 300 kms of galleries coming from ancient quarries which sleep under the feet of the Parisians
These one are forbidden to visit since 1955.
you can have a look on them : http://kata.addict.free.fr