Valerie L.
Google
Fascinating and very clearly done. You have to join a tour - they do ones in English by arrangement, but I didn't bother as I went on spec. The tour is in 3 sections, and all were very relaxed. I found the first the most interesting because you saw the hammer working (it's noisy!) and the guide spoke extremely clearly. I had to wait to go in but only because the tours started on the hour.