About ten years later, as a result of the Franco-Prussian War, the affected states became part of the German Empire, so it was agreed to build the Neckargemünd–Neckarsteinach–Eberbach–Neckarelz–Jagstfeld line, which was opened on 24 May 1879.

[3] After the Neckar bridge was blown up in 1945 at the end of World War II, the halt of Neckarbrücke was established near Kleingemünd on 9 March, allowing trains to run to the east.

Since then, the Neckar Valley Railway has used the route through the 2487-meter-long Königstuhl Tunnel, which had previously only used freight trains to the Heidelberg marshalling yard.

[6] From the 1950, many of Deutsche Bundesbahn's main lines were electrified including the Neckar Valley Railway between Heidelberg and Heilbronn.

In early 1996, the track was adapted for DM 18 million for the use of tilting Regional-Express services and equipped with the Geschwindigkeitsüberwachung Neigetechnik (GNT) system.

[8] Until the introduction of the new train designations (RE/RB) there were mainly local trains on the line, but also three pairs of Heckeneilzuge ("hedgerow expresses", that is they stopped at all stations on rural sections, but ran as expresses near cities) ran from Frankfurt via Hanau and Erbach to Stuttgart and from Eberbach to Heilbronn over the Neckar Valley Railway.

All stations of the Neckar Valley Railway served by the Rhine-Neckar S-Bahn have been rebuilt to provide barrier-free access for the disabled and equipped with protection from the weather.

Some major stations (for instance, Eberbach and Neckarelz) were retrofitted with LCD destination displays a few years before the launch of S-Bahn services.

Increasing the platforms to 76 cm above the running surface made possible a level entrance to the class 425.2 S-Bahn electric multiple units.

In Neckarsulm, there is a four-minute connection to the shortened Regionalbahn services to Stuttgart, which also reach Heilbronn Hbf faster because they do not pass through the city centre.

But private transport companies also operate freight on the Neckar Valley Railway, for example, TX Logistik, Häfen und Güterverkehr Köln and BCB.