Hidden beneath cities and landscapes worldwide lie tunnels once shrouded in secrecy. These tunnels served military, political, or strategic purposes and were closed off to the public for decades. Today, many have been rediscovered and transformed into fascinating tourist attractions. Visitors can now explore these underground passageways, gaining insight into history, engineering, and espionage. Here are ten formerly secret tunnels open for public exploration.
1. Cu Chi Tunnels, Vietnam
The Cu Chi Tunnels near Ho Chi Minh City were a vital network used by the Viet Cong during the Vietnam War. Stretching over 120 miles, these narrow tunnels functioned as hiding spots, supply routes, and living quarters. Visitors can crawl through portions of the tunnels, see hidden trapdoors, and learn how the underground system sustained soldiers during intense conflict. Exhibits include authentic wartime artifacts and demonstrations of guerilla tactics. The site serves as a powerful reminder of resilience and ingenuity.
2. Wieliczka Salt Mine, Poland
While primarily a salt mine, the Wieliczka complex includes secret tunnels and chambers carved over centuries beneath Krakow. Used for mining and sometimes refuge, the tunnels feature chapels, statues, and intricate carvings all made from salt. Open since the 13th century, this UNESCO World Heritage Site lets visitors explore a subterranean world with guided tours highlighting its geological and cultural history. The mine’s secretive past as a vital economic resource adds to its allure.
3. Edinburgh Vaults, Scotland
Beneath Edinburgh’s Old Town lie the Edinburgh Vaults, once hidden underground chambers used in the 18th and 19th centuries. These tunnels served as workshops, storage spaces, and housing for the city’s poorest residents. Forgotten for over a century, the vaults were rediscovered and opened for tours showcasing their dark past involving crime, poverty, and illicit trade. The eerie atmosphere and historic artifacts provide a glimpse into Edinburgh’s underground life long ago.
4. Burlington Bunker, England
Constructed during the Cold War, Burlington Bunker was designed as a secret government command center capable of housing hundreds of officials in the event of nuclear war. Hidden beneath the Mendip Hills, this enormous complex remained classified for decades. It has since been decommissioned and partially opened to the public. Visitors can explore the extensive tunnels, communication rooms, and living quarters, gaining insight into Cold War fears and preparations.
5. Cu Chi Tunnels, USA – The Greenbrier Bunker
Beneath the Greenbrier Resort in West Virginia, a massive Cold War bunker was built to serve as a secret evacuation site for the US Congress. It remained classified for over 30 years until its exposure in the 1990s. The bunker includes over 100,000 square feet of tunnels and rooms with sleeping quarters, offices, and a medical center. Today, tours reveal the extensive planning for government continuity in times of crisis.
6. Paris Catacombs, France
Originally limestone quarries, the tunnels of the Paris Catacombs became a mass burial site in the late 18th century to alleviate overcrowded cemeteries. The labyrinth extends for miles beneath the city, with walls lined by millions of skeletal remains arranged artistically. While some areas were closed for safety, many sections are open to the public as eerie tourist destinations. The catacombs tell a unique story of Paris’s history, death, and urban development.
7. Odessa Catacombs, Ukraine
The Odessa Catacombs are among the largest labyrinths in the world, extending approximately 1,200 miles beneath the city. These tunnels were originally limestone mines but became vital during World War II. Soviet partisans used them as hideouts and bases against Nazi forces. Guided tours take visitors through selected areas, showcasing wartime artifacts and stories of resistance. The tunnels remain a testament to survival and strategy.
8. Shanghai Tunnels, USA
Under Portland, Oregon, the Shanghai Tunnels have a controversial past linked to the practice of “shanghaiing,” where men were kidnapped and forced into maritime service. The tunnels connect the city’s basements to the waterfront, facilitating covert movements. Now open for public tours, the tunnels explore tales of crime, smuggling, and maritime history, giving a darker side view of Portland’s past.
9. Cu Chi Tunnels, USA – Denver’s Underground
Denver, Colorado, has an underground network of tunnels once used for utility lines and storage, but some sections were reportedly used during Prohibition for illegal activities. These tunnels were forgotten but have recently been partially uncovered and opened to visitors. Tours share stories about bootlegging, speakeasies, and the city’s underground economy during the early 20th century.
10. Cappadocia Underground Cities, Turkey
Beneath the fairy chimneys of Cappadocia lie vast underground cities such as Derinkuyu and Kaymakli. These multi-level complexes were carved out to protect inhabitants from invasions. Secret tunnels connected living quarters, kitchens, stables, and ventilation shafts. Open to tourists, these ancient tunnels reveal extraordinary underground architecture dating back thousands of years. Visitors marvel at the ingenuity used to create self-sustaining subterranean refuges.
