Physically demanding mountainbike tour from Osterode am Harz to the Hochharz and back over the Oberharz and the Harz-foreland Along the beautiful water reservoir Sösetalsperre, the route with deciduous and mixed forests starts with one long ascent through the Sösetal valley, up to the Acker mountain in the Hochharz. From here it goes up through a valley to a single trail, which shows the untouched nature and many views to the Brocken across the Nationalpark Harz. The route continues with a long descent from Torfhaus to the water reservoir Okertalsperre in the Oberharz. The next ascent leads to the Oberharz summit 'Schalke' from where wide views over the Oberhharz are possible. The route then leads mostly downhill over the town of Hahnenklee and through the towns of Wildemann and Bad Grund into the Harz foreland. At the edge of the Harz the forest ends and it goes over hills and fields back to Osterode.