We went in July 2017. They had tours then. We paid for the tour, but we ended up just walking ahead. The tour guide was very slow. We had to wait for a significant time to enter a building (a handful at a time). We were told that if we left the tour, we could not rejoin. There are plenty of explanatory signs. They were enough for us.
We did not do a tour. Whike there we walked through everything on our own. Although this last trip up there was still a lot of snow and you were not able to drive to the mine area. You could walk back if U wanted however we did not. Our last trip was June 8th 2018.
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