Horyn River [Horyn’]. (Map: Horyn River.) A right-bank tributary of the Prypiat River. It has a length of 659 km, a width of 20–80 m, and a depth of up to 16 m; its basin covers an area of 27,700 sq km. The Horyn's lower stretch is navigable. The upper Horyn dissects the Volhynia-Kholm Upland and the Polisia Lowland. The Sluch River is the Horyn's largest tributary.