In 1830, the Kanonenhof was built as a defensive position between the fortress and the adjoining town fortifications to the south. Next door in the laboratory, with vaulted rooms and an earth roof, rifle and gun ammunition was manufactured. In 1943, the war laboratory was converted into the air raid control center of Deutsche Werke. From 1960 to 1990, the building served as a warehouse for the combat groups of the Optima office machine factory.