The area includes the valleys in the middle course of the Krumovitsa River and its tributary Djushun Dere with the adjacent hills and slopes of the Eastern Rhodopes. It covers the sections of the Krumovitsa between the village of Gorna Kula and the mouth of the Djushun Dere, from where it reaches the grounds of the village of Chal to the east. The Krumovitsa river valley in this region is between 300 and 1000 m wide, at places occupied entirely by the sandy riverbed itself. There are differently expressed belts of riverine tree vegetation mainly of poplars (Populus spp.), willows (Salix spp.), black alder (Alnus glutinosa), etc. It is mixed with shrub vegetation of blackberry (Rubus spp.), dog rose, etc. At many places shrubs, mainly of Tamarix spp., and grasses grow in the riverbed itself.