Prisoner-of-war camp
During World War II the fortress served as Prisoner-of-war camp (Oflag VII „b” 1939-1941, Stalag 367 1941–1945). It was used as a prison for Polish officers imprisoned by the Germans. Notable prisoners included Counter Admiral Stefan Frankowski, General Tadeusz Piskor and Rear-Admiral Józef Unrug. After the war, the fortress was parts of the lands transferred from Germany to Poland. In 1961 it was added to the Polish register of objects of cultural heritage. In 1973 a military museum was opened in the Fort. In 2002 it was declared a culture park, and in 2004 it was recognized as a Historic Monument ("Pomnik historii").