The Secret State Archives Prussian Cultural Heritage Foundation (German: Geheimes Staatsarchiv Preußischer Kulturbesitz or GStA PK) is an agency of the Prussian Cultural Heritage Foundation headquartered in Berlin, Germany. A Federal statutory body, it is one of the largest repositories of primary source documents in Germany and spans the history of Prussia, Brandenburg, the House of Hohenzollern and the Prussian Army. Insofar as the agency represents over 400 years of archival work of the former states of Brandenburg-Prussia, including their main roots in the Teutonic Knights, the Archives can be said to cover "nine centuries of European history between Königsberg and Cleves."[1]