High Quality Content by WIKIPEDIA articles! The Aar Valley Railway (German: Aartalbahn) is a 53.7 km long line between Wiesbaden, the capital of the German state of Hesse, and Diez in Rhineland-Palatinate. From 1985 to 2007, the southern end was operated as a heritage railway with historic trains. The Hessian part of the line is heritage-listed. Currently, two bridges are unusable and several sets of points are defective and need to be repaired. Its northern end is operated with draisines.