Dora 1, Trondheim

Dora 1 holds a significant place in Trondheim as a reminder of World War II. It represents a time marked by military strategies and the challenges of wartime construction. Originally built by the Germans as a submarine base, known as DORA I, it played a crucial role in their naval operations during the occupation of Norway.

Construction on Dora 1 began in 1941, a year after Germany invaded Norway. This was part of a larger plan to improve naval capabilities in occupied areas, offering better repair and operational facilities than Norway had before the occupation. Its location in Trondheim, referred to as Drontheim in German, was strategic, providing access to the Atlantic and Arctic Oceans.

Dora 1 was designed to be part of the largest German naval base in Northern Europe. It was heavily fortified, with a 3.5-meter-thick concrete roof reinforced with steel and 3-meter-thick walls. This was to protect the U-boats from aerial attacks, which was a significant concern during the war.

During the war, Dora 1 housed the 13th U-boat Flotilla, with 55 U-boats assigned to it, highlighting Trondheim's importance as a U-boat base in Norway. Plans were made to expand the submarine base with Dora 2 and Dora 3, but only Dora 2 was partially completed by the end of the war.

After the war, Dora 1 was repurposed for civilian use. It became a warehouse, and workshop, and housed the city and state archives, as well as a bowling alley and various businesses. The submarine pens were turned into a harbor for civilian boats.