Passenger services were reactivated on the southern section between Radolfzell and Stockach in 1996 and has since been operated under the brand name of Seehäsle.

Since 2021, trains have once again been running between Stockach and Mengen on Sundays and public holidays under the brand name of Biberbahn.

[4] These committees planned a new line from Ulm via Ehingen, Riedlingen, Mengen, Meßkirch, Stockach, Radolfzell, Singen, Schaffhausen, Waldshut and Säckingen to Basel and a branch from Meßkirch via Tuttlingen and Donaueschingen to Freiburg and beyond via the Rhine and the Vosges as far as Chaumont.

[3] In 1866, the loose German Confederation collapsed, but the sovereign states of the Grand Duchy of Baden, the Kingdom of Prussia and the Kingdom of Württemberg signed trilateral treaties to promote the "transnational" rail project and its passage through the Prussian Hohenzollern Province.

Prussia did not seek to build its own railway in southern Germany but wished to see the two main cities of the province connected to the rail network of the neighbouring countries.

In the park the remnants of the rail sidings and piers of the Ablach bridge mark the formerly double-track line.

Prussia also achieved a connection of the railways of neighbouring countries to the Hohenzollern Province in Hechingen without having to build its own rail network.

On 1 November 1873, a fast pair of trains was introduced, requiring 100 minutes to run from Radolfzell via Mengen to Ulm,[5] but in 1875 it was abandoned for lack of profitability as there was little demand.

[7] On 24 July 1944, fighter-bombers attacked a freight train loaded with cattle between Bichtlingen and Meßkirch and a farmer and livestock trader and businessman from Messkirch was killed.

Here, the rails were removed from the Krauchenwies station premises to the connection with the siding to Dillmannschen sawmill near Mengen.

On 29 September 1986, at the initiative of the Tegometall company, the Krauchenwies–Mengen section was returned to service after it had been rebuilt with state subsidies for freight.

The district of Constance (Konstanz) rented the section between Stahringen and Stockach from Deutsche Bahn, which let it fundamentally reorganise it.

Due to frequent breakdowns of the GTW sets, a variety of replacement vehicles were used from 2001: these included a MAN railbus set (class VT 98 + VS 98) of the Hochwald Railway, a RegioSprinter of the Rurtalbahn GmbH and Regio-Shuttles of the Hohenzollerische Landesbahn (HzL).

The GTW prototypes were sold through an intermediary to the Italian company Ferrovie del Sud Est.

Since they have been replaced by new Regio-Shuttle diesel multiple units (and the NE 81 sets were transferred to Südwestdeutsche Verkehrs-Aktiengesellschaft).

Traffic is controlled from the HzL Ringzug (ring train) operations centre in Immendingen, where the railcars are also maintained.