Paris Top 30 Attractions - One-Two-Go Paris: The Quick Guide to Paris 2015 - page 256

You decided to move on; the underground is waiting for you!
The Paris Catacombs are basically a long hollowed out series of tunnels where bones have
been piled up. You will walk through a really claustrophobic series of tunnels with human
skeletons as “decoration”.
Walls of carefully arranged bones