Tunnels, caves, bunkers, mines, and tombs—there’s a whole world right below your feet.
You can scale the highest mountains, take a plane around the world, and dive into the deepest parts of the ocean, but often forgotten are the sights right below your feet, hidden beneath cobble-stoned streets and under barren landscapes. Some are breathtakingly beautiful, while others might send shivers down your spine. From tunnels carved in wartime by to a natural cave filled with a galaxy of stars, we have the 10 most fascinating places underground (and you don’t have to be a scientist to see them).
Churchill War Rooms
Hidden beneath the streets of London lie the Churchill War Rooms, where former British prime minister Winston Churchill, his cabinet, and military personnel directed the course of the Second World War. Now part of the Imperial War Museums, the underground bunker protected the staff and their secrets during the tense days and nights of the conflict. After the war, the historic value of the complex was recognized immediately and some places like the Map Room have remained exactly as they were left on the day the lights were turned off in 1945. The museum includes the sleeping quarters, Churchill’s swivel chair, and historic maps and documents.
Located in Brazil’s Chapada Diamantina National Park, Poço Encantado (Enchanted Well) is an easily accessible cave with an underground lake and a natural window out to the jungle. At certain times of day between April and September, the sunlight falls in through a crevasse and hits the crystal clear water in the cave turning it a deep, mysterious blue. Below the surface, ancient tree trunks and rock formations appear very close despite the water’s depth of 200ft. Poço Encantado is a fragile ecosystem so unfortunately, you’re not allowed to have a swim.
Magma Chamber of Thrihnukagigur Volcano
From mid-May to mid-October, you have the chance to journey towards the center of the earth in Iceland. After a 40-50min hike across Thrihnukagigur’s lava field, the moment of truth arrives when the open cable lift descends 394ft into the maw of the volcano, which last erupted 4000 years ago. The trip down or up takes about six minutes, and time spent on the ground is about 30 minutes.
INSIDER TIPIf you suffer from claustrophobia, this is a bad idea.
Waitomo Glowworm Caves
WHERE: New Zealand
One of the must-see attractions on New Zealand’s North Island, the Waitomo Glowworm Caves are famous for their stalactite and stalagmite displays, and the presence of millions of native glowworms that hang from the cave walls and ceilings. In the cave system, carved through limestone by underground streams over the last 30 million years, the tiny creatures radiate a whitish-blue luminescent light that attracts prey like moths and other small insects that get caught in the glowworms’ sticky threads of silk. The highlight of each guided walk is the boat ride through the pitch black Glowworm Grotto where the sparkling cave ceiling will make you think you’re standing right under a galaxy of stars.
Salt was first extracted from the Turda Salt Mines in 1075, and the mine was open through the Middle Ages until its closure in 1932. Salina Turda was reopened in 1992 as a subterranean museum and halotherapy center to treat respiratory problems with the mine’s ionized air, pressure, and humidity. It is located 368 ft below the surface and has huge underground halls (the biggest one being 295ft in height and 285ft in diameter). Highlights of Salina Turda include an Echoes Room, a “cascade of salt”, an underground lake, stalactites (some are 10 ft long) and the Crystal Hall.
Cu Chi Tunnels
The Cu Chi Tunnels underneath northwest Ho Chi Minh City are a 75-mile long underground complex that were used by Viet Cong soldiers as hiding spots, supply routes, and even living quarters. Two different tunnel display sites, Ben Dinh and Ben Duoc, were modified for tourist access (i.e. the walls were made wider and taller for Westerners) and you can crawl and crouch in safe parts of the tunnel system or try a meal that the fighters would have eaten. The original underground complex was several stories deep in parts and included entire weapon factories, field hospitals, and kitchens.
César Manrique Foundation
If you think you’ve seen all sorts of living quarters by now, from converted barns to igloos—think again! On the island of Lanzarote, renowned artist César Manrique (who was friends with Picasso and Miro) built himself an incredible residence in the 1960’s. Below the white, Spanish-style house sits a basement that interconnects five underground lava bubbles and features elegantly-designed rooms bored into volcanic basalt. No need for wallpaper or windows in this abode. The central, open air space houses a small cacti garden, a swimming pool, and a BBQ area. The house in Tahiche is a most unusual living space within a natural landform and attracts about 300,000 visitors annually.
Tomb of Seti I
Easily dwarfing other Egyptian tombs, the final resting place of Pharaoh Seti I is the largest, deepest, and most completely finished in the Valley of the Kings. It was discovered in October 1817 by Italian Giovanni Battista Belzoni and recent excavations revealed it to be about 120 ft longer than originally thought. Seti I’s tomb comprises eleven chambers and rooms and all but two contain well-preserved paintings and reliefs depicting the king’s introduction to the underworld and scenes from the Book of the Dead. Over time, wall panels and scenes were removed and now form part of collections in Paris, Florence, and Berlin.
Caverns of Sonora
WHERE: Texas, US
Called the “the most indescribably beautiful cave in the world” by the founder of the National Speleological Society, Bill Stephenson, the Caverns of Sonora in Texas amaze with an array of calcite crystal formations. Guided tours take visitors through almost two miles of highly-decorated cave passages some 155 feet below the surface. Perhaps the most delicate of cave formations (so watch your head and limbs), helictites form shapes known as fishtails, saws, rods, or butterflies. One spot in the cave, which has been open to the public since 1960, is so densely packed with mineral formations, it was nicknamed the “snake pit.”
Coober Pedy is sometimes referred to as the “opal capital of the world” thanks to the abundance of the gemstone mined there. The remote town in South Australia is also known for its “dugouts”, below-ground residences in which about half of the population of 3,500 live in order to escape the scorching heat (often in excess of 104 °F). If you’re up for it, you can stay in an underground hotel, eat in subterranean restaurants, and visit the two underground churches (Serbian Orthodox and Catholic). Or how about playing golf at night with glowing balls on a course that is completely grass free? Make sure to take your own piece of “turf” with you for tee off!