U-Boot-Stützpunkt Drontheim

Trondheim in the middle of Norway was from June 1940 until liberation in May 1945, the largest German naval base in Northern Europe. Here, the German marine 13th u-boat flotilla had its headquarters,

There germans built two u-boat bunkers, Dora I and Dora II, it was only Dora I that was finished when the war ended.

Construktion of Dora I started in 1941, and when it was completed 2 years later, it measured 502 x 344 feet, and the 5 u-boat pens had space for 16 u-boat. The walls were 10 feet and the ceiling 9.8 ft thick and made of reinforced concrete.

Dora II measured 550 x 335 feet, and was construkted with 4 u-boat pens.

Dora I was after the war expanded to 2 floors, and is today used as a warehouse and a bowling alley.

Dora II was so badly damaged by Allied bombing that half of the roof after the war was blown away.

The Germans named their bases by location and Trondheim in German is Drontheim, "D" in the German phonetic alphabet is Dora.