Some of the world’s most breathtaking travel destinations may be hidden in the ground beneath your feet.
While some are man-made constructions, others are fascinating natural wonders that have been formed over the course of thousands of years.
We’ve put together a list of 24 subterranean attractions to visit in your lifetime, from a 10,000-year-old cave in Playa del Carmen, Mexico, to a town that built a library, church, bar, and homes underground.
Salina Turda, located in Turda, Romania, is home to an underground theme park inside one of the oldest salt mines in the world. Head 400 feet down to reach an amphitheater, bowling alley, mini golf course, ping pong courts, Ferris wheel, and an underground lake with row boats.
Bounce Below is a set of three giant trampolines nestled inside the Llechwedd Slate Caverns -- a former Victorian slate mine in Blaenau Ffestiniog, North Wales. It was created by Zip World, a company specializing in adventure activities.
The company also built Zip World Caverns, which is also situated in what used to be mines near the town of Blaenau Ffestiniog in Gwynedd. Guests are suspended up to 100 feet down into the slate cavern.
The Postojna Cave in Postojna, Slovenia, is known for its whimsical web of tunnels, passages, galleries, and halls, all of which have a stunning diversity of karst formations. The cave also has several entertainment options, including a concert hall and a train that operates through part of the cave.
Inside the Formosa Boulevard Station in Kaohsiung, Taiwan, is a 4,500-panel glass artwork by Narcissus Quangliata that is said to be the largest glass-work in the world. Thanks to the stunning kaleidoscope effects of the piece, the area has actually been used as a wedding venue.
More than 90 of the subway stations in Stockholm, Sweden, have been decorated with sculptures, mosaics, and paintings. The Kungsträdgården metro station houses the relics of the old Stockholm Makalös palace and has an impressive industrial-looking design.
Thanks to temperatures that can reach as high as 104 degrees Fahrenheit, almost all of the residents of the South Australian town of Coober Pedy live underground. The town's residents have created a fascinating submerged world, where you'll find everything from an underground bookstore to a subterranean church.
The Salt Cathedral of Zipaquira, Colombia, sits 590 feet below the surface in the heart of a salt mine. Carved salt sculptures and a 16-foot cross adorn a cathedral that gets some 3,000 visitors each Sunday.
Hidden beneath Paris, France, are the Catacombes de Paris -- an eerie network of caves and tunnels housing the remains of nearly 6 million people. Considered the world's largest grave, the catacombs have attracted thousands of visitors, including King Charles X and Napoleon III.
The Batu Caves of Selangor, Malaysia, feature stunning temples and paintings that depict Hindu gods. Before entering the caves, marvel at the enormous statue of Lord Morugan in the entrance.
The Basilica Cistern in Istanbul, Turkey, was built by Byzantine Emperor Justinian I. The royal reservoir is said to be able to store up to 24 million gallons of water. Explore its stunning design as you admire its 336 marble columns and its two head of Medusa sculptures.
In the deep salt mine of Wieliczka, Poland, altarpieces, chandeliers, and even the ornamented Chapel of St. Kinga were chiselled out of rock salt. According to Travel + Leisure, tours began in the 14th century and have included guests like Copernicus, Goethe, and President George H. W. Bush.
The mine also hosts an underground sanatorium and curated events, including concerts, theatre performances, galas, and fashion shows.
The Dambulla Cave Temple (also known as the Golden Temple of Dambulla) is the largest and best-preserved cave-temple complex in Sri Lanka. Inside, there are Buddhist mural paintings covering entire walls and more than 150 statues dating back centuries.
In Turkey's Cappadocia region, there's an array of fascinating subterranean safe houses that were carved from rocks of volcanic ash. Several historic underground cities have been discovered many levels below the surface, revealing networks of tunnels, inclined corridors, and stepped pits.
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