The Kriva river is the longest river in this region, it is 75 kilometres long, and by the river basin area (1,002 km2) it is the largest tributary of the river Pčinja.

 It springs in the mountains of Osogovo, north of Carev Vrv, at an altitude of 1,932 meters, and in Pčinja it flows near the village of Klečovce, at 294 meters above sea level.  

From the source to the mouth of the Kiselichka river, 18 km from the source, the river Kriva first flows to the north and northwest, then abruptly changes its direction and continues to flow southwest.

 In the centre of Kriva Palanka, the Kriva river receives its largest tributary, the Duračka River. The Kriva Reka valley is composite, with several modified parts of the gorge. Zidilovsko – Palanecka, Psačka, Marko’s gorge, Vakufska gorge with erosive continuations: Uzemsko, Trnovečko, Sredorečko and the valleys: Slaviškaka and Kumanovska valley. The Zidilovka gorge on the Kriva river stretches for 11 km, between the villages of Uzem and Kriva Palanka.

This gorge is 200-300 meters deep and not very steep. It is mostly covered in forest vegetation, but in some areas, there are stone offshoots of different shapes, sizes and interesting looks. Corridor 8 passes through Zidilovska gorge, which is an opportunity for tourists to stop for rest, observation, photography, hiking, etc.