The Hessel is a 39.3-kilometre-long, right tributary of the River Ems in the territory of the North Rhine-Westphalian districts of Gütersloh and Warendorf in northwest Germany. The river rises northwest of Halle on the Große Egge, crosses the Hermannsweg, flows through the villages of Hesseln and Hörste in Halle borough, then through the borough of V…The Hessel is a 39.3-kilometre-long, right tributary of the River Ems in the territory of the North Rhine-Westphalian districts of Gütersloh and Warendorf in northwest Germany. The river rises northwest of Halle on the Große Egge, crosses the Hermannsweg, flows through the villages of Hesseln and Hörste in Halle borough, then through the borough of Versmold through Oesterweg, continuing through the town of Sassenberg and along the southern edge of Milte in the borough of Warendorf, before emptying into the Ems near Warendorf-Einen.