If you don’t mind a little road trip for an amazing adventure, we can strongly recommend you to go to Setesdal Mineralpark in Hornnes wich is ca. 1 hour away from us.
We have been there ourselves, and we got very surprised over what we got to see. When you enter and walk under the ground, you will see a lot of our earths hidden treasures.
The owner him self, Arnar Hansson, told us that on several occations he has been letting guests inside that were doubting if they would want to pay to see that. Each and every one of them paid on the way out,
and they thought that the experiense was worth the money. If you meet the owner you maybe can ask him for the same? We think that either way you will gladly pay when you leave, because then you have seen something very special.
Setesdal Mineralpark offers a lot of activities, like boat renting, bathing, trre climbing, zip lining, and a lot more. Have a look at their website here.