The World’s Coolest Underground Attractions

The remains of more than 6 million bodies lie in the labyrinth of the Paris Catacombs 20 meters beneath the city’s streets. The city's overrun cemeteries in the 18th century led the government to begin moving the dead to underground locations, inadvertently creating a spooky spot that has been attracting tourists for generations.

The Wieliczka Salt Mine, a UNESCO World Heritage Site, was one of the oldest salt mines in operation until it ceased production in 2007. Hand-carved caves and brine lakes mark the fascinating trip 500 feet beneath the medieval town of Wieliczka. Just a half-day trip from Krakow, tours of the mine dive deeper into its history, where you can marvel at the ornate chapel of the Blessed Kinga, whose intricate details are made from salt deposits.

A 4.5 hour trip from Bucharest, the Salina Turda—known as the largest salt mine in the world—has been transformed into a subterranean amusement park 368 feet (120 meters) underground. The depths for entertainment and relaxation are limitless: an underground lake for boating, a halotherapy spa, and even a bowling alley.

Rated as one of the top things to do in London, England, The Churchill War Rooms is a fascinating look into the bunker that sheltered then-Prime Minister Winston Churchill and his war cabinet from German bomb raids and was used as the headquarters to strategize the allied route to victory during the Second World War. Don’t miss the Map Room, which has remained in the same condition as it was in 1945.

The 20-mile (32-kilometer) network of shops, restaurants, and other entertainment attractions lies underneath the streets of downtown Montreal. It is a refuge in the city’s freezing winter months and ideal for a souvenir pick-up or something for yourself. It's more than just a mall, and the longer you spend perusing, the more you'll forget that there's actually no sun or sky in sight.

The iconic sinkhole of Cenote Ik Kil, a popular pit-stop en route to Chichen Itza, is a unique way to “dive deep” into Mexico’s subterranean culture. Descend into a limestone carved stairway, accented with hanging vines to the swimming platform, where you can jump into a pool that is 40 meters deep.

Founded by two teenagers while running after a ball during a cricket match, the Crystal & Fantasy Cave is one Bermuda’s most stunning natural wonders. The dripping stalactites and shimmering Cahow Lake when lit make for a fun photo opportunity.

The Dambulla Cave Temple—also known as The Golden Temple of Dambulla—is the largest and best preserved cave-temple complex in Sri Lanka. Five caves house the highlights of this UNESCO World Heritage Site, including a 100-foot-tall Buddha gilded in gold at its entrance; mural paintings encompassing the cave walls, and more than 150 statues honoring Buddha, gods, goddesses, and royalty.

These famous caves are about a 2.5-hour drive from Auckland. Waitomo is a Maori word, which can be translated as the "stream which flows into the hold in the ground" and it is exactly what you’ll experience in this underground cave illuminated by its high population of glowworms.

As one of the busiest transit systems in the world, Moscow’s metro serves up to 9 million passengers a day. In the Cold War era, stations like the Mayakovskaya Metro Station were built as shelters in the case of a nuclear war beneath its glamorous baroque architecture.