Don't go there without a map or a brochure of things that you can visit in Kongsberg because it can happen that you have no chance to enter the tourist office. It happened to me!! I went there at 1 p.m. and the office was closed; strange because in Italy most of the offices stay open from 8 a.m. to 8 p.m.
By the way this is the address of the tourist office, better to know it before arriving there!