The route is currently operated by a regular service of Deutsche Bahn RegionalExpress trains, using double-decker rolling stock, which allow excellent views.

For many localities, which, prior to the advent of train service, were only accessible via horse-drawn carriages, this development was key to their industrialization.

From the end of the 19th century, until World War I, the manufacture of clocks in the Black Forest saw its economic heyday, and this industry marks the local economy even today.

Not only the residents of towns directly on the line, such as St. Georgen, Hornberg, Villingen-Schwenningen, and Donaueschingen, were beneficiaries of train service, but even Furtwangen or Schramberg, which are not far away, profited.

However, these initial plans did not come to fruition, mainly because the technical expertise necessary to build this complex and expensive line was not yet available.

Geological issues in the Wutach Valley prevented taking a path in a southerly direction from Donaueschingen, and trains took a lengthy detour around the Swiss Canton of Schaffhausen to reach Singen, near Lake Constance, which was the ultimate destination.

After settling on Offenburg as the starting point, and Singen as the destination, three variations on the line were examined: The Bregtallinie option was eliminated first, due to its expense and complexity.

From an engineering perspective, it was actually the Schiltachlinie that turned out to be easiest to execute; however, because that line would have run through Schramberg, in Württemberg, and would not have been located solely in Baden, the final decision was made to utilize the Sommeraulinie.

To deal with the watershed between the Rhine and Danube rivers, the Hattinger tunnel had to be dug through the local limestone.

Due to the further delays caused by the Franco-Prussian War in 1870, the Black Forest Railway was not completed in its entirety until 10 November 1873.

In addition, the section Singen–Konstanz, which had been opened in 1863 as part of the Baden Mainline, was operationally linked to the Black Forest Railway.

Plans were also drawn up to connect the Elz Valley Railway from Freiburg via Elzach with Hausach, but this was never realized.

Starting in 1924, the old Hornberg viaduct across the Reichenbach valley was replaced by a new arched bridge to increase the capacity of the route.

The damage was repaired just a few weeks after the end of the war, and the Black Forest Railway was operational again on 30 June 1945.

Rail buses were seen on the Black Forest Railway for the first time in the summer of 1955, and the following year marked the first service of diesel locomotives on the line.

It is also worth noting that, due to the many sections with steep inclines, locomotives of the type DB Class 139, with rheostatic brakes, were prominently seen in service.

Invitations to bid on providing local rail service between Karlsruhe and Konstanz were issued in 2003 across Europe by the state of Baden-Württemberg.

Starting on 10 December 2006, trains consisting of locomotives of the type DBAG Class 146, and modern double-decker passenger cars with the name "Schwarzwaldbahn" printed on them, are providing comfortable service with air conditioning and suspension seats.

On weekends, an additional IC train with numbers 2004 and 2006/2005, dubbed "Bodensee", connects Konstanz with Dortmund, Emden, and Norddeich.

The section between Offenburg and Gengenbach is flanked by expansive vineyards, which slowly dwindle away as the Kinzig Valley narrows.

From Hornberg to Sankt Georgen, the route must negotiate numerous loops, many through tunnels, and transcends several hundred metres in altitude in the process.

The route passes through numerous tunnels (37 alone in the section between Hausach and Sankt Georgen), but only travels across one large viaduct, in Hornberg.