By Clive Freeman Jun 27, 2007, 7:31 GMT
Berlin - It's called the Teufelsberg - Devil's Mountain - and after World War II it became the loftiest man-made hilltop in Berlin, when 16 million square metres of rubble from the devastated German capital were dumped there.
In the postwar era it was crowned by a huge intelligence facility, complete with antennas and radar domes like giant golf balls - reputedly for monitoring troop movements and tapping military phone links to Moscow in the communist era.
Today, however, it is what lies beneath the Teufelsberg that has been arousing curiosity.
Back in 1937, Hitler showed up there to lay the foundation stone for a vast military academy designed by Albert Speer, the Nazi dictator's favourite architect.
There were visions of it being a military equivalent of Britain's Oxford University and forming part of 'Germania' - the Nazis' never-to-be realized dream of a '1,000-Year Reich' capital.
But 'war-specific problems' halted work on the academy in 1940, according to an internal Nazi memorandum.
When troops of the four victorious powers occupied Berlin in 1945, the British military government considered using the unfinished structure for administrative purposes, but later dropped the idea.
Ultimately, the British requisitioned a cluster of buildings surrounding the Nazi-built Olympic Stadium and transformed them into a military headquarters.
The existence of the Teufelsberg military academy buried under the 116 metre-mountain was forgotten until recently when the Association of Berlin Underworlds discovered documents relating to it.
The organization, which has also discovered Nazi bunkers and tunnels, has announced plans to dig into the mountain to find the 'last undiscovered secret that underground Berlin has to offer.'
Dietmar Arnold, the Underworlds' co-founder, is convinced most of the military school is intact, despite efforts made to blow up the building at war's end.
A team, he says, plans to penetrate the north-eastern face of the mountain and dig until it strikes the concrete outlines of the Nazi Academy. 'We know for sure that underneath there is also a massive multi-storey bunker complex,' he adds.
In post-Berlin unification years, there were rumours of either a large hotel and recreational facility or a spy museum being built on the Teufelsberg. Neither materialised.
Once a workplace for some 150 US and British intelligence officials, the spy facility became a forlorn relic in the 1990s, costing 35,000 dollars a month just to keep empty.
Arnold claims that during the Nazi era close on 1,000 underground bunkers were built in Berlin. Many were subsequently destroyed, but dozens survived. Underworlds has uncovered 50 of them in the past decade, he says.
Aware of the public's fascination for bunkers and hidden wartime tunnels, it has made a computer-animated reconstruction of Hitler's final bunker retreat, down to the last window frame and door handle.
This is where he brought a brutal end to his life, as the Red Army arrived to throw a cordon around the capital in the spring of 1945.
The Underworlds' virtual tour of the Hitler Bunker, based on security records, has been acclaimed by historians as the 'most reliable, existing impression of the Fuehrer's underground refuge.'
Located off the city's Wilhelmstrasse, the bunker was finally blown up in the late 1980s and a kindergarten has now been built above the site.
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