Railways:

The Main-Neckar Railway (German: Main-Neckar–Eisenbahn, MNE) is a main line railway west of the Odenwald in the Upper Rhine Plain of Germany that connects Frankfurt am Main to Heidelberg via Darmstadt, Bensheim and Weinheim. It was opened in 1846 and is one of the oldest railways in Germany.

The Main-Neckar Railway was built and operated as a joint state railway company, known as a condominium railway (Kondominalbahn), by the Free City of Frankfurt, The Grand Duchy of Hesse-Darmstadt and the Grand Duchy of Baden.

https://en.wikipedia.org/wiki/Main-Neckar_Railway

From Frankfort to Heidelberg:  The Rhine from Rotterdam to Constance (1878) Route 28  page 194