Ghosts of the NSA: Relics of Cold War Spying Dot Germany
Tracking down traces of the National Security Agency in Germany isn't particularly difficult. One merely has to head to Berlin and look for the city's highest point. It can be found in the southwest corner of the city -- Teufeslberg, or "Devil's Mountain." Made of piled up rubble gathered from Berlin following World War II, the "mountain" rises 115 meters (377 feet) above the nearby waterway known as the Havel.
In the winter, it is the place where Berliners meet to sled; in the summer it is a haven for mountain bikers and daytrippers. And hobby historians: At the very top of the hill stands the most famous NSA relict in Germany -- five gigantic white radar balls. The listening station was used until the end of the Cold War, primarily to spy on the east.
Teufelsberg used to be part of the NSA's global espionage network called Echelon, which the US intelligence service used to keep an eye on Moscow. From 1957 to 1991, the NSA maintained a presence on Teufelsberg and eavesdropped on satellite-based telephone conversations, filtered fax reports and analyzed Internet datasets. The NSA was still doing all that in 2013, as SPIEGEL recently reported, but it no longer requires the massive radar towers.
http://www.spiegel.de/international/germany/ghosts-of-the-nsa-cold-war-listening-stations-across-germany-a-909652.html