The catacombs of Paris

Beneath the streets of Paris are the famed catacombs. Originally a series of quarries built in Roman times, the tunnels were first used for the gory purpose in the late 1700's, when mass graves in standard cemeteries were blamed for the spread of disease. In the second World War, both the French Resistance and the Nazis used the catacombs for their own purposes.

In current times, the catacombs have become a popular tourist destination, accessible through a rather low-key street level door. Once through the entrance visitors descend a circular stairway to the tunnels below.

The scene once you're there is both eerie and intriguing. Bones are piled against the walls, many segregated by type (arms and legs in one pile, skulls stacked in another), and all piles labeled with a sign noting which cemetery they came from, and when. You could just reach out and touch them, but there's that feeling that a bony hand might reach out to touch you back.

Once you've walked through the open portion of the catacombs, you take another stairway up to street level. It's all rather pedestrian, except for the very end. Just before you go outside, you're stopped by two gatekeepers who stand before a sign with the international "No" symbol drawn over a crudely drawn skull and crossbones. The gatekeepers insist -- in French -- on examining your bags to see if you're trying to smuggle out a souvenir.

As if. Try explaining to the TSA what that tibia-shaped thing is that they scanned in your carry-on luggage.