The Fischbach Valley Railway (German: Fischbachtalbahn, KBS 681) is a railway line in the German state of the Saarland that runs from Saarbrücken along the Fischbache, which flows into the Saar in Saarbrücken, to Wemmetsweiler. Since the opening of the Wemmetsweiler curve in 2003, the line branches west to Lebach as the Prims Valley Railway (Primstalbahn) and east to Neunkirchen.