Catacombs, Paris

The catacombs are situated by Denfert-Rochereau metro and is the renovated section of caverns and tunnels which are the remains of the Paris stone mines - it became a tourist attraction from the early 19th century; the history of the walls of bones and skulls is fascinating although macabre, I can't believe that its taken me almost 10 visits to Paris before I've finally investigated.