The Kütiorg Valley is the biggest and grandest primeval valley of Estonia (length 4.7 km, width 250–600 m, depth 50–75 m). It has been formed as a result of erosion by subglacial flowing waters which were under a great pressure in the Ice Age. In a deep steep-edged valley, the Iskna Creek flows through six small lakes and reservoirs. The valley is characterised by steep-edged additional valleys (Lambahannatsori, Süvaorutsori, Tammetsori, Rebasetsori, Juudijeeratus). The edges of the Kütiorg Valley are covered with spruce and mixed forests where spruces, which are more than a hundred years old, as well as thick and tall rare aspens grow. The Kütiorg Valley can be visited by using a hiking trail with the same name.