In 1915, the building (until 11.11.1918) was used as a site for a flight guard. During the Second World War (from 1940) the building was used by the German Wehrmacht as Richtfeuerstelle. After the war, the tower served from 1945 to 1955 as a radio control center for the British military. It was not until 1955 that it was open to all visitors as an observation tower. (Source: bismarcktuerme.de)