From President John F. Kennedy's top secret Cold War bunker and Winston Churchill's War Rooms to Hitler's Führerbunker, the scene of his demise, and the fallout shelter Stalin would have retreated to in the event of nuclear Armageddon, the world's most (in)famous hideaways have some intriguing stories to tell. 

Click or scroll through to explore 10 of the most notable underground fortresses of all time...