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
History of the Jews in Cologne community in Cologne. The region was occupied by the Franks in 462, which converted to Christianity by the end of the century. During the Middle Ages, Cologne flourished as one of the most important trade routes between east and west Europe. Cologne was one of the leading members of the Hanseatic League and one of the largest cities north of the Alps in medieval and renaissance times. The first documentary reference to the Jews in Cologne in the Middle Ages was to the time of Archbishop Heribert of Cologne (999-1021), the wise friend of Holy Roman Emperor Otto III. Winheim