The Enz Valley Railway (Enztalbahn or Enzbahn) is a 23.6 km (14.7 mi) long railway line in the northern part of the Black Forest in the German state of Baden-Württemberg. The line runs from Pforzheim to Bad Wildbad and for its course runs close to the River Enz. The line was opened by the Grand Duchy of Baden State Railway on 11 June 1868 and is one of the oldest railways in Germany. It is now integrated into the Karlsruhe Stadtbahn as line S 6.