Wollenberg near Bad Freienwalde was the site for one of 26 tropospheric radio transmission centres operating under the code name “TUSHURKA“ within the Eastern Military Bloc. In 1984 work commenced on the construction of a 2-storey edifice to house the radio and transmission technology in the Semmelberg – at 158 metres the highest point of elevation to the east of Berlin. This was intended to enable communications to be maintained even in the wake of an atomic attack. Mobile communications technology was also used for this purpose. When it was completed in 1987 the installation was surrounded by a high voltage fence. In 1990 the Federal Armed Forces briefly took over the site, which, from 1992 onwards, was variously used as a centre for asylum seekers, a disaster control centre and an industrial site. It stood empty from 1999 onwards until the “Special Site 301Wollenberg” with its significance in terms of military history was acquired by a society. Since 2004 this society has been organising guided tours of the facilities featuring old-style technical equipment as well as the collection of military vehicles.