Mysterious Underground Tunnels and Bunkers for the Adventurous Traveler

23. The Nuclear Bunker Under Stockholm – Sweden’s Cold War Time Capsule

Deep beneath the city of Stockholm lies Pionen, a former nuclear bunker turned state-of-the-art data center. Originally built during the Cold War to withstand nuclear strikes, the bunker has been transformed into a futuristic underground facility that looks straight out of a sci-fi movie. The facility features glass-walled conference rooms, waterfalls, and even a simulated sun—designed to create a livable environment in the event of a disaster. While the bunker itself remains largely off-limits to the public, its existence highlights the lengths to which governments went to prepare for nuclear catastrophe.