Historical Archive of the City of Cologne up at the site of the collapse (a large hole in the ground), where around 95% of all archival items could be held until August 2011, albeit scattered and in many cases badly damaged. Archive repositories all over Germany offered space to store the damaged and only roughly cleaned documents: wet materials were flash-frozen to prevent mold growth. "Itinerant archivists" worked in the receiving archives all over the country and began the task of re-identifying and re-cataloging. A newly installed centre for restoration and digitization on the outskirts of Cologne started working in 2011, with a total cost for restoring
NS Documentation Centre of the City of Cologne the best pre-served prisons from the Nazi era, representing an historical asset of national and European importance. Since June, 1997, the permanent exhibition in the EL-DE building has depicted political, social and community life in "Cologne During the Nazi Era." That includes the seizure of power and the power apparatus, propaganda and the "national community," everyday life, youth culture, religion, racism, the genocide of Cologne's Jews and its Sinti and Roma, and opposition, resistance, war and society during war. In addition, temporary exhibitions depict local and national aspects of the Nazi regime. The center also mounts more than 130 events