Damaged Goods
From Aksat’s account and those of others, much of the underground network of this structure is not explorable without oxygen masks. There was a fire at some point, leaving behind poisoned air and dangerous passageways.
Railway
Beneath where floorboards once made the hallways walkable, rails from long gone railway clue us into a discarded train system. At one time, the Nazis used these rails to move heavy items in or out. The floorboards are long since gone, but the rails remain.