The Natura 2000 site “Kalltal und Nebentäler” (DE-5303-302) [Kall Valley and its side valleys] forms the background to the project. It lies in the Eifel, in the south-west of the federal state of Nordrhein-Westfalen (NRW), extending from the German-Belgian border near Monschau to where the Kall flows into the Rur, near the bunter sandstone rocks at Nideggen. Along the way the landscape shows many faces. On its upper stretches the valley is broad and open, since the streams here have only slightly cut into the ancient bedrock at the foot of the Hohes Venn (Hautes Fagnes). Near Simmerath the Kall Valley takes on the typical U-form, and its quite steep bordering slopes are mostly still used as meadows and grazing land. Around Simonskall however the water has finally cut deep into the landscape. The steep, often rocky slopes are generally forested.