Background Following the occupation of Norway in 1940, it was soon realised that the country only had limited facilities for minor naval repairs. More extensive work usually meant a return to Germany. The
capitulation of France two months later overshadowed the strategic importance of Norway to some extent, but it was still regarded as a better location for access to the
Atlantic and
Arctic Oceans than Germany. Nevertheless, better protection for U-boats from aerial attack was required so a bunker-building programme was instigated.
German U-boat bases in occupied Norway operated between 1940 and 1945, when the
Kriegsmarine (German navy), converted several naval bases in Norway into submarine bases.
Trondheim was an important U-boat base in Norway during the war. It was the home of the
13th flotilla and it had 55
U-boats assigned to the flotilla during its service.
Construction The German civil and military engineering group,
Organisation Todt, started constructing the facility as a submarine base as they were finishing
Dora I (completed in June 1943). Construction of Dora II began in 1942 The second bunker was a little more than half complete by the time the war ended. If finished it would have been long by wide, ==After World War II==