Jeker (-Dutch, in French: Geer) is a river in Belgium and the Netherlands. It is a tributary to the river Meuse. The source of the Jeker is near the village Geer in the Belgian province Liège. Most of its course is in Belgium (provinces Liège and Limburg), except the final approx. 5 km in the Netherlands (province Limburg). The Jeker flows into the river Meuse, in the city Maastricht. Cities along the Geul are Waremme, Tongeren (both in Belgium) and Maastricht (Netherlands).