13 Abandoned Cold War Bunkers Hiding Incredible Secrets

5. Teufelsberg Listening Station, Berlin, Germany: Spies on Devil's Mountain

Perched atop a man-made hill built from WWII rubble ("Devil's Mountain"), Teufelsberg housed a crucial US National Security Agency (NSA) listening station during the Cold War. Its iconic geodesic domes concealed powerful antennas used to intercept Soviet, East German, and other Eastern Bloc communications. Now abandoned, the site is covered in graffiti art and offers panoramic Berlin views. Its secret is its tangible link to Cold War espionage – a silent sentinel that eavesdropped across the Iron Curtain, now an eerie, decaying monument to intelligence gathering.