Batterie Dietl was built during WW2, the works started in 1942. The area had 3 of the largest and most expensive guns ever made by the germans, the Adolf Cannons, with 40.6 cm calibre. The cannon barrel itself was 21.5 meter long, weighing 158 tons! and could shoot its 600 kilo ammunition across the Vest Fjord all the way to Lofoten, effectively covering any access to the harbor of Narvik. The manual labour was done by approx. 2000 russian POWs and 3000 of other nationalities. Of the russian prisoners, 514 died during the construction time. Between 5000 and 7000 germans was stationed on Batterie Dietl during the war.
The guns never engaged in actual warfare, only test shots were ever fired from them.