It was opened in 1910 to connect the historic Siegburg–Olpe railway directly to Cologne and required the construction of the Hoffnungsthal tunnel.

The section from Hoffnungsthal to Rösrath partly used the track of the Cologne–Lindlar railway, which is now largely disused west of Bergisch Gladbach.

The planners of the Siegburg–Olpe railway preferred a direct connection to Cologne from the beginning rather than the indirect route via Siegburg.

In these difficult years the line was also used by many of the starving urban population to buy food (on Hamsterfahrten, literally “hamster rides”).

The line was also affected by the increasing motorisation and a systematic reduction in services by the Bundesbahn and other rationalisation leading to losses of passengers.

At the beginning of the 1980s, after the closures of the Agger Valley Railway between Lohmar and Overath and Dieringhausen and Olpe, the remaining line was at risk of being closed.

Since 1991, the Oberbergische Bahn has run in Cologne on the newly built S-Bahn trunk line on the Köln Hansaring–Cologne Hauptbahnhof–Köln Messe/Deutz–Köln Trimbornstraße route.

The announced reconstruction of Dieringhausen station (on the Volme Valley Railway) to provide barrier-free access has still not been implemented.

In addition to a facility of Regionalverkehr Köln (a regional bus operators owned by various municipalities), the building houses a newly opened restaurant and rooms for social and cultural events.

In 1984, ten class 218 locomotives of the Hagen depot were repainted to match some Silberling carriages in pure orange (RAL 2004) with a pebble grey belly band for the CityBahn project and were used as push–pull trains in regular intervals services on the Cologne–Meinerzhagen route.

[9][10][11][12] Since 1999, services on the route have mainly been provided by diesel-electric multiple units of class 644 (Bombardier Talent) in double or triple traction.

Today the line from Cologne via Overath and Dieringhausen is operated as part of the Rhine-Sieg S-Bahn with a Regionalbahn service (RB 25: Oberbergische Bahn) over the Agger Valley Railway and Volme Valley Railway to Marienheide: Fares on the whole route are set by the Verkehrsverbund Rhein-Sieg (Rhine-Sieg Transport Authority, VRS).