Yeah, “underground” sounds like dark tunnels and flashlight horror, but that’s not the full story. It turns out some of the wildest and most unforgettable places on Earth are hiding right under your feet. Now, slow travel is the name of the game—no packed resorts, no TikTok-famous spots swarming with selfie sticks. These underground gems are way cooler (literally), more peaceful, and 100% unforgettable. We’re talking salt cathedrals, ancient cities, cold-war bunkers. Real places. Real experiences. Real good reasons to go below ground.
Salt Cathedral of Zipaquirá, Colombia
Not your average Sunday church. This place is built inside a salt mine—yep, 650 feet underground. Imagine flickering lights bouncing off carved altars, massive salt crosses glowing in the dark, and air so still it feels sacred. You’ll walk through 14 chapels carved into rock salt. It’s a full-on experience, not just a photo stop. Tickets run about $15. Go mid-morning, dodge school tours. And yeah, bring a hoodie. It’s chilly in there.
Derinkuyu Underground City, Turkey
You ever crawl into a tunnel and suddenly feel like you’re in another century? That’s Derinkuyu. What looks like boring farmland in Cappadocia hides a giant underground city, eight stories down, packed with rooms, stables, and even a church. Some of the tunnels are so tight you’ll walk sideways. Claustrophobes, skip it. Adventurers, go. Entry is around $5. Get there early, as this place is popular and not made for crowds. Also, wear grippy shoes; those stairs are steep and slick.
Wieliczka Salt Mine, Poland
Think of it as Hogwarts meets Minecraft, but salty. This place is enormous—chapels, chandeliers, even an underground lake, all carved from salt. And yes, it’s all real. The tour takes you 2.5 miles in, past ancient tunnels and a cathedral that literally glows. They even host concerts down there. Entry runs about $25. Want pics? You’ll need to pay a small camera fee (cash only). Oh, and bring comfy shoes. It’s a hike.
City Hall Subway Station, NYC, USA
You can’t walk through this abandoned subway station, but you can ride through it. Just stay on the downtown 6 train after its final stop at Brooklyn Bridge, and you’ll loop through this stunning space with skylights, tile work, and vaulted ceilings. Want a close-up? The NYC Transit Museum offers occasional guided tours, but spots fill fast. You need to sign up for alerts months in advance.
Cu Chi Tunnels, Vietnam
Near Ho Chi Minh City lies a labyrinth of tunnels that housed soldiers and civilians during the Vietnam War. Some passageways are preserved in their original size (very tight), while others are widened for tourists. You’ll see trapdoor examples, kitchens, and even crawl through parts yourself. Entry runs $10–$20. Mornings are best; afternoons bring crowds and heat. Bring bug spray.
Edinburgh Vaults, Scotland
Under the South Bridge lies a maze of stone vaults used in the 18th and 19th centuries for shops, storage, and possibly smuggling. Some sections are dark and atmospheric, others eerily silent. Day tours focus on history, while night tours lean spooky. You choose the vibe. Book online to secure a spot. It’s uneven down there, so wear good shoes.
The Lowline Lab, NYC, USA
Though the original lab closed in 2020, the world’s first underground park is coming back—bigger and better. The new Lowline Park, using solar-reflecting tech to grow real plants below street level, is expected to reopen in 2025. It’s located in an old trolley terminal beneath the Lower East Side. Watch for announcements around late summer. Free entry is planned but may require advance reservations.
Coober Pedy Homes, Australia
This opal mining town in South Australia is blazing hot, so locals moved underground. “Dugout” homes, churches, and even hotels keep temperatures steady around 75°F year-round. You can tour a real underground house, check out the mine museum, and sleep in an underground hotel. The Desert Cave Hotel is a popular pick. Reachable via regional flights or long-distance coach.
Seattle Underground Tour, USA
Seattle’s original downtown was buried after an 1889 fire, and the city rebuilt on top. Today, you can walk the old sidewalks below Pioneer Square. The tour guides make it funny, weird, and historical all at once. Tickets are about $22. Go midweek for fewer crowds. Heads up: no restrooms during the tour—go before you go.
Svalbard Global Seed Vault, Norway
Located 800 miles from the North Pole, this secure facility stores millions of seed samples as a backup for global agriculture. It’s not open to the public, but visitors can hike to its entrance for a photo op and visit the nearby Svalbard Museum to learn about the vault. Dress for sub-zero temperatures, even in summer. Travel requires planning: fly through Oslo to Longyearbyen.
Postojna Cave, Slovenia
Ride a tiny train into Slovenia’s most visited cave, filled with cathedral-like chambers, curtains of stalactites, and translucent creatures called olms. Tours last about 90 minutes and are offered in multiple languages. You can also bundle it with Predjama Castle nearby. Tickets cost around €28 for the combo. The caves remain around 50°F—bring a jacket.
Montreal’s RESO, Canada
Locals call it the Underground City, and it connects over 20 miles of shops, hotels, and metro lines beneath downtown. It’s designed to help people escape harsh winters, but it’s also just convenient. Perfect for museum-hopping without stepping outside. Best time to explore? Winter months (December–March). Grab a map—first-timers get lost easily.
Paris Catacombs, France
More than six million bones are stacked in tidy rows beneath Paris, arranged in decorative patterns inside an old quarry system. Only a small portion is open to the public, but it’s unforgettable. Online reservations only. Don’t expect cell service underground, and wear good shoes. It’s damp and uneven.
Batu Caves, Malaysia
You’ll smell incense, hear chanting, dodge pigeons, and probably get side-eyed by a monkey—all before you even reach the top. Batu Caves isn’t just a temple; it’s an experience. Those 272 rainbow-colored steps? They’re no joke, especially in the Malaysian heat. But the views? Worth it. Time your visit with Thaipusam if you want the full festival vibe. Just pack patience and water. And seriously, do not feed the monkeys—they’re not shy or polite.
Vardzia Cave Monastery, Georgia
Carved into the cliffs of southern Georgia, this ancient monastery complex features tunnels, chapels, and dwellings spread across 13 levels. It was built to hide monks from invaders and includes secret passageways and frescoes still intact today. Closest city: Akhaltsikhe. Allow at least 3–4 hours to explore, especially if you’re climbing to the higher sections. Wear hiking shoes.
