13 Abandoned Cold War Bunkers Hiding Incredible Secrets

6. Balaklava Submarine Base (Object 825 GTS), Crimea: The Hidden Fleet

Carved deep into the mountainside near Balaklava, this colossal underground complex was a top-secret Soviet base for servicing and sheltering nuclear submarines. Designed to survive a direct nuclear hit, it featured a hidden canal system allowing submarines to enter directly from the sea, disappear into the mountain, undergo repairs, and reload torpedoes, all completely concealed from spy satellites. Its secret is the sheer scale and audacity of constructing an invisible, nuclear-proof submarine lair – a Bond villain-esque feat of engineering.