I cycled up the tallest, most fearsome peak in the whole of Berlin at midnight last night. Teufelsberg is a 120 m high mountain in the former West Berlin, built from 75,000,000 m3 of rubble deposited there after the war. Buried underneath the mountain is an incomplete Nazi military-technical school designed by Albert Speer.
The USA’s NSA organisation decided it would be a great idea to build one of their largest spy installations on top of the mountain during the 1960’s. The original spy domes and their protective fencing are still there.
I can neither confirm nor deny if someone may have breached the outer perimeter to inspect the domes at close range 😉