Zeppelin Bunker sealed up after WW2: The key communications center of the Third Reich
Spaç Prison: a witness to Albania’s communist days
The story of the fort San Juan de Ulúa and its rat-and-flea-infested dungeons
The derelict Radiotechnical School – a victim of food shortages
The Steam Train Graveyard: Used to be a secret location should war break out
The Abandoned Soviet Military Communications School in 50 Amazing Images
