Mining began in the 1350s and the mine had its heyday already in the 15th century. Mining continued on and off to varying extents until the end of the 19th century when the mine was filled with water. Between 1915 and 1920, mining resumed temporarily, it took 2 years to pump the mine free of water.

There is no comprehensive system of locations at submersible depths, but it is still very difficult to orient yourself. We know of 3 shorter mine shafts in the Great Mine at 16, 30 and 40 meters deep, all shorter than 10 m. In the western part of the Great Mine there is a plateau about 5 meters deep that divides the submersible part of the mine into 2 parts. Under this plateau, you can swim through relatively narrow passages from one part to the other in at least 2 places. These are located at 16 and 40 meters respectively. about 22 meters deep.

At the western end of the mine there is a passage under the road over to the Källgruvan mine. You go down into the Källgruvan through a shaft that then widens. The depth is reportedly about 40 meters, but at a depth of about 35 meters, visibility becomes non-existent. Visibility is also greatly impaired by air bubbles tearing sediment from the wooden structures that support the shaft.

Immediately east of the large mine there is a machine/elevator shaft that is reportedly about 250 m deep.

Visibility varies greatly depending on precipitation. Rain and meltwater wash away sand and mud. The conditions are therefore at their best after a long dry period.

ROV dives carried out by the police have shown that there are several cars at a depth of about 60 meters in the Large Mine.