It did not pursue this project for long because the Kingdom of Württemberg had begun negotiations with the Grand Duchy of Baden in order to build the Nagold Valley Railway from Pforzheim.

On 13 August 1865, the parliament of Württemberg decided to build the Black Forest Railway from Zuffenhausen via Leonberg to Calw.

The State Railways built Weil der Stadt station north of the town.

The opening of the second part of the line from Ditzingen to Weil der Stadt took place on 1 December 1869.

The difficult section through the Black Forest to Calw, was put into operation by the State Railways on 20 June 1872.

Nevertheless, the Reichsbahn electrified the Black Forest Railway on 18 December 1939 to Weil der Stadt.

The locomotives used to haul through trains from Stuttgart to Calw and vice versa were changed in Weil der Stadt.

Deutsche Bundesbahn operated Uerdingen railbuses between Weil der Stadt and Calw until 29 May 1983, when passenger services were abandoned.

For years, the Calw district and the Association of the Württemberg Black Forest Railway, Calw–Weil der Stadt (Verein Württembergische Schwarzwaldbahn Calw–Weil der Stadt) have tried to have the line reactivated, if necessary or appropriate, by extending line S 6 to Calw.