There is a point on the B4 where the forest stops pretending and the Harz shows its real face: open moor, stunted spruce, grey sky and, on a clear day, the bald dome of the Brocken on the horizon. Torfhaus is a cluster of buildings on that high plateau, at about eight hundred metres, built around a car park, a few cafés and a visitor centre for the Harz National Park. It has the feel of a place on the edge of something, which is accurate, because until 1990 the inner German border ran only a short distance east, and the Brocken beyond it was a closed military zone with listening posts on the summit.
The Brocken, at 1,141 metres, is the highest peak in northern Germany and the great stage of German witch lore. According to tradition, witches gather on its summit on the night of 30 April, Walpurgisnacht, and Goethe set a famous scene of Faust there. The mountain is famous for its weather, with fog on most days and snow into May, and from Torfhaus you can see why. In winter the plateau becomes a cross-country ski area, and the road can be slick with ice or closed by snow, so check conditions. Fog and wind are the standard setting; on a bad day you can lose sight of the road edge.
The ride from Bad Harzburg is the part that matters. The B4 climbs from the lowland town through beech and spruce in a series of confident, well-surfaced curves, then levels out on the moor. It is a road for a steady, relaxed pace, with a view of the sky and the odd stag. There is a lot of traffic on dry weekends, including lorries and cyclists. On the other side, the road descends toward Braunlage, a larger resort with more places to eat. The Harz is the northernmost of the German uplands, so the weather arrives from the North Sea with little to stop it, and you should treat even a summer ride with some respect.
Cafés in the village serve sausage and hot drinks. A short walk onto the moor shows how the peat bog holds the water, with cotton grass in early summer and a dark, slightly sinister stillness around the pools.
In winter the whole area goes quiet and white, and you will see more snowshoes than motorcycles.