Since we’ve already descended deep into America’s urban underbelly, this time we’re exploring the complex subterranean mazes below the streets of world’s biggest metropolises. Here are nine of the coolest underground cities beneath actual cities.
The mines and catacombs
This is one of the oldest, creepiest networks known to the world, spanning hundreds of miles of old caves, tunnels, and quarries beneath the French capital. Much of its infrastructure has been illegally explored by “cataphiles” (the word for local urban spelunkers) like the secret society les UX, who’ve even set up underground cinema clubs and art installations over the years. One of the most famous graffiti areas is called La Plage or The Beach, a random sandy area highlighted by a Japanese mural. The more official, legal-to-explore part of the catacombs is its subterranean cemetery available on public tours. Here you can see the bones of 6 MILLION people along walls, behind glass cases, and even freakily arranged into skull and shinbone designs.