The Rhine Feeder is a river system that consists of four rivers: the Ruhr, MOSEL, AAR, and AARE. The Ruhr is a river in western Germany that flows into the Rhine. The MOSEL is a river in Germany, Luxembourg, and France that also flows into the Rhine. The AAR is a river in Switzerland that flows into the Rhine. The AARE is a river in Switzerland that also flows into the Rhine. Together, these four rivers form the Rhine Feeder, which is a major contributor to the Rhine River.