The two belong to the same story. The Upper Harz was one of the great silver and lead mining districts of Europe, and its engineers built an astonishing network of ponds, ditches and tunnels to bring water to the wheels that drove the pumps and hoists. That water system is part of the UNESCO listing, which took in Rammelsberg and Goslar in 1992 and was later extended to cover the Upper Harz. Today the ponds look like natural lakes, and it takes a moment to realise that someone dug every channel by hand.
Clausthal-Zellerfeld is a town of around fifteen thousand at some 600 metres, and it has the largest wooden church in Germany, the Marktkirche. The building is a huge, light and surprisingly warm interior, and the town has a technical university with roots in the mining academy. Winters are long, snow often lasts into March, and in summer the streets are busy with Harz walkers. For riders, there is fuel here, plenty of cafes and a base from which to make the plateau loops.
The riding is great in the right season. The Harz plateau is a place of spruce forest and open clearings, with well-surfaced roads that climb through bends and descend to river valleys. B242 and B241 are the main routes, with quieter roads to Wildemann and the Innerste valley, where forest falls steeply to a little river. Fog is common, and so is wet leaf mulch after autumn storms. A good tip is to wait for a clear morning after rain, when the whole forest smells of resin and wet earth. In summer it is a few degrees cooler than the plains, which can be a relief.
Around the town, the old mining ponds such as the Oderteich are worth a detour, with reflections of the spruce in still water. Stop for a coffee in Zellerfeld and look at the cut stone of the old administrative buildings. This is a landscape made by labour, and once you notice the ditches running along contours, you start to see them everywhere.