Considering the Sonnenhotel Kreuzeck in Goslar?
A VT member wrote the following comment about visiting Goslar:
Lohmühle - Leather Tanners' Mill by Kathrin_E
In former times, dozens of water mills operated along the streams in the old town. The water running down from the mountains provided the power for them. Only one mill wheel is still there and turning: that of the Lohmühle, the leather tanners' mill. Built in the late 16th century, it served for grinding the oak bark that was needed for leather tanning. Inside, most of the historical mechanism is still there but can only be seen either by appointment with the Goslar Museum or during a guided city tour.