The Harzer Schmalspurbahnen is a meter gauge line in the Harz mountains of Germany.  Its headquarters are in Wernigerode,with lines to Brocken peak, Nordhausen, and Quedlinburg.      It was built primarily as a forestry railway, but evolved as part of the general rail transport system, and finally became basically a tourist railway, although it continues to provide a modest amount of local transportation.  One branch, the "Brockenbahn" climbs to the top of Brocken, the highest peak in central Germany and in the middle of the Harz National Park.  Brocken peak is in former East Germany and close to the old border with West Germany, and during the Cold War was an important Soviet intelligence gathering station.   Today it is a popular summer and winter recreation area.  From Wernigerode to Brocken there is frequent tourist service, but service on the other lines is much more limited.  The passenger trains are steam powered for the most part, but there are several diesel engines and a small fleet of diesel raillbuses.