Paris Catacombs, Paris, France

Bones and skulls are stacked on either side of a narrow corridor like merchandise at a warehouse—a lot of merchandise. The air is close and cool, with just a hint of decomposition, and there's rude graffiti dating from the French Revolution, mainly about the king and the feeble nobility. Once inside, you can easily see why Victor Hugo and Anne Rice have set stories in Paris's famous Catacombs. Snaking some 187 miles through underground passages around the city, only a tiny portion is open to the public—it's said that the rest is patroled by the legendary cataflics, a special underground police force. Though guided tours are available, it's more creepy and effective to go on your own, when it's just you and millions of bones lit by the occasional low-wattage bulb. The catacombs were originally a Roman-era quarry, but when the Innocents Cemetery in central Paris started overflowing to the point of being a public health hazard in 1785, the tunnels came into their present state. Bones were carted off in elaborate nighttime ceremonies, and until 1814 the catacombs filled up with Paris's dead. You can reach out and rattle the ivory yourself if you like, but the greatest chill is in wondering which of them didn't die of natural causes.

Paris Catacombs
Tel: 33 1 43 22 47 63