Unearth the World Below: Exploring Subterranean Wonders
We live in a three-dimensional world. Yet, while our instinct is often to look up, sometimes the best stories can be found by looking down. From caves and tunnels to bunkers and futuristic infrastructures, there’s a huge variety of fascinating and awe-inspiring subterranean places to travel to around the world.
Chris Fitch, author of Subterranea: Discovering the Earth’s Extraordinary Hidden Depths, lists a selection to add to your (post-pandemic) bucket list, proving that the world below our feet is every bit as vivid and evocative as that we see around us.
Yucatán Cenotes – Mexico
Sixty-six million years ago, an asteroid struck what is now Mexico’s Yucatán Peninsula. The impact triggered a super-tsunami that swept the globe, ending the reign of the dinosaurs. Today, the outer rim of the 112-mile diameter crater left behind is visible from overhead maps, revealing around 900 deep holes in the ground. Known as “cenotes,” these chasms expose spectacular pools of clear, mineral-rich freshwater below.
This water is so naturally clean and drinkable that it sustained the ancient Mayan empire for 3,000 years. Perhaps the most famous example is the 115-ft-deep sacred cenote at Chichén Itzá, a UNESCO World Heritage Site and significant tourist attraction.
However, there are hundreds of diverse and beautiful cenotes scattered across the landscape, and swimming in them is a popular activity when visiting the Yucatán. Self-driving or private taxis offer the best options for travel between these often remote locations. Many have tourist facilities and personal guides available on-site, for a small fee.
Chauvet du Pont d’Arc – France
Regrettably, none of us can visit the real Chauvet du Pont d’Arc cave. Ever since three explorers (including local ranger Jean-Marie Chauvet) discovered the oldest known cave drawings in the world in late 1994, access has been strictly controlled.
Being cut off from the outside environment for between 29,000 and 37,000 years, experts fear that allowing tourists inside would destroy the delicate, sophisticated artworks adorning the walls, ruining them forever.
Consequently, visitors to Chauvet du Pont d’Arc are directed towards a perfect replica constructed nearby. The many exotic animals depicted on the walls—mammoths, lions, rhinos, and more—evidence that such creatures once coexisted with early humans in this region tens of thousands of years ago. Over 1,000 drawings have been carefully copied and are on display.
The standard cave tour lasts around an hour and includes a multilingual guide and a simulation of the sensory environment experienced inside the real Chauvet du Pont d’Arc, such as low lighting and distinctive smells.
Derinkuyu – Turkey
If modern cities appear impressive, wait until you’ve taken a tour around Derinkuyu, probably the largest and most stunning of the 250 subterranean settlements carved into the landscape of Cappadocia, located in the Anatolian plateau of modern Turkey.
Dating back an estimated 4,000 years, this labyrinth of homes, stables, churches, and more is almost invisible from above. Yet, once inside, it unfolds into an intricate and sophisticated network of tunnels below ground.
Complete with vertical shafts to aid airflow and facilitate inter-level communication, Derinkuyu was home to 20,000 people. The main purpose of this and other underground Byzantine cities was primarily defensive, as a tactic to evade invading forces.
The hidden entrances were equipped with rolling boulders to trap attackers, alongside mechanisms like scalding hot oil ready to be poured from above. This hideaway remained so well concealed that its precise location was lost for centuries, rediscovered only when a modern resident stumbled upon a mysterious passageway behind a wall in his home. Additionally, regular buses from the nearby Nevşehir town provide one transport option to reach the site.
Kazumura – United States
A lava tube, such as Kazumura, is a river of molten rock where the exterior cools and hardens while allowing hot liquid lava to flow through the center. In 1981, Kazumura, on the island of Hawai’i, was measured at just over seven miles, making it the longest lava tube globally. Furthermore, in 1995, four nearby tunnels were confirmed to be part of the same massive lava tube, stretching over 40 miles between the upper slopes of Mount Kilauea and the Pacific Ocean.
This kapu (sacred) subterranean space is believed to have formed during a 60-year eruption in the 15th century, according to a timeline proposed by geomythologists, who combined indigenous island mythology with contemporary empirical data. The tunnel features a ceiling up to 59 feet high, dripping with bizarre worm-like “lavacicles.” It has over 100 known entrances and descends almost a full mile in altitude from volcano to coast.
Moreover, small group tours are available to help visitors navigate the potentially treacherous conditions within Kazumura, which include jagged rocks and perilous hidden cavities.
Coober Pedy – Australia
The Australian desert is famously an insufferably hot place. Summer temperatures can soar to 50°C (122°F) or more in the South Australian town of Coober Pedy, making survival itself a risky prospect. This begs the question of why 3,000 Australians call this town home, located 528 miles from the state capital of Adelaide.
The answer lies in opals. These valuable translucent stones were first discovered by aspiring gold prospectors in February 1915, leading to a continuous influx of miners on the hunt for opals, making Coober Pedy the proud “opal capital of the world.” To combat the extreme conditions, these miners did what they knew best: they went underground.
Visitors to the remote settlement may initially feel they’re in the wrong place due to limited visible signs of life from ground level. It’s only upon discovering the remarkable homes, shops, hotels— and even a museum and a casino— dug into the earth itself that this subterranean town reveals its true nature.
Multiple generations have lived their lives in these below-ground residences, enjoying the cooling effects of the surrounding sandstone, which maintains a comfortable 73°F even as temperatures rise above. Organized tours to explore the hundreds of working opal mines can typically be arranged through the Coober Pedy Visitor Information Centre.
Large Hadron Collider – Switzerland/France
Come see the place where the world didn’t end. Despite apocalyptic headlines, the Large Hadron Collider (LHC), activated in September 2008, did not create a black hole; rather, it enabled a series of scientific breakthroughs that revolutionized humanity’s understanding of physics.
The circular 17-mile tunnel buried beneath the city of Geneva provides a venue for scientists at Franco-Swiss CERN (European Organisation for Nuclear Research) laboratory to fire particles around at almost the speed of light.
Moreover, collisions between these particles have led to monumental discoveries, such as the fabled Higgs boson, essential to our understanding of the universe and controversially nicknamed the “God particle.” Upon completion in 1988, the LHC tunnel represented Europe’s largest civil engineering project.
Operating at -465°F, the tunnel is almost a complete vacuum— devoid of atmosphere. Free daily two-hour tours (by reservation only) are conducted by CERN, providing an opportunity to explore this extraordinary scientific facility.
