Dora I

Dora I is a former German submarine base and submarine pen or bunker built in Trondheim, Norway. Construction of the bunker was undertaken during the Second World War. Nearby is the uncompleted Dora II . Trondheim was traditionally referred to as Drontheim in German, and the name DORA is the letter "D" in the German phonetic alphabet.
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.

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