The uranium mining region is made up of areas of extensive mining activity that shaped wide swathes of the western Erzgebirge. An important aspect of the region is the decontamination and redevelopment of the remnants of the uranium-mining period from the second half of the 20th century until today. The uranium mining that took place in the Erzgebirge following the Second World War is globally unparalleled. It was prompted by the Cold War and the nuclear armament of the Soviet Union. From 1950 onwards, mining activity in the area gradually developed into a planned operation under the central control of the Soviet-German uranium company SDAG Wismut. The mining areas around the towns of Johanngeorgenstadt, Schneeberg, Schlema, and Hartenstein were of particular importance. After 1945, SAG Wismut, the central administration for uranium mining in Saxony, was beholden to the Soviet authorities. From 1953, it was operated as SDAG Wismut – with Germany holding only a minority stake in the company. In both its scope and its impact, the uranium mining carried out by SDAG/SAG Wismut exceeded all previous mining activities in the Erzgebirge. Uranium mining was discontinued after the reunification of Germany in 1990.