Since so many of you were curious about the listening station, I thought I'd post a few pictures with a better overall view. Teufelsberg is located in what was formerly the American sector of Berlin. During the Cold War, devices that could intercept communications from the Russian sector of Berlin (East Berlin) were housed inside those bubbles, officially known as radomes.
The listening station has been abandoned for many years now. There was a proposal to destroy the old buildings and build a hotel on the site, but the plan was opposed by Berliners. Today the space is run by a group of street artists who give guided tours of the site. They hope to eventually raise enough money to turn the space into an artist's retreat and gallery of sorts. We'll see where the future takes us... You can read more about Teufelsberg and the listening stations by clicking on the links above.