Kongsberg Silver Mines
The silver mines of Kongsberg, in Buskerud county in Norway, constitute the largest mining field in Norway, with over 80 different mines. It was the largest pre-industrial working place in Norway, with over 4,000 workers at its peak in the 1770s and supplied over 10% of the gross national product of the Danish–Norwegian union during its 335-year-long history: over 450,000 man-years were expended in the production.
Stordø Kisgruber
Mining for pyrite at Litlabø had first been estgablished in 1865. Stordø Kisgruber A/S was established in 1907 and maintained mining operations which ended in 1968. A total of about eight million tons of ore was won during the operation of the mine. Under the elevator tower is the main mine shaft which went straight down about 750 meters deep. Altogether there are 80 km of shafts into the mountain. A railway line operated between Litlabø and the quays at Sagvåg.
During the Nazi occupation of Norway, the mines delivered pyrite to Germany for use by the country's war industry. During 1941, this amounted to 9,000 tons per month. In January 1943 the mines were targeted by the British Commando raid Operation Cartoon. Several dynamite charges were set off in various buildings at Litlabø. The hoist machine, the compressor house and the locomotive engine shed, among others, were blown up.