Line S 13 is a S-Bahn line of the Rhine-Ruhr network. It is operated by DB Regio. The S13 runs from Horrem, at peak times, via Cologne to Troisdorf. Normal operation begins at Köln Hansaring. It runs with Line S 12 for most of its route, splitting from it only to run through Cologne/Bonn Airport. Services operate every 20 minutes on working days and every 30 minutes on Saturdays, Sundays and public holidays, using class 423 electric multiple units.
Line S19
6 additional pairs of services in the morning peak and 11 additional pairs of services in the afternoon peak have run on the Horrem – Köln Hansaring – Cologne – Cologne/Bonn Airport – Troisdorf– Siegburg/Bonn – Hennef (Sieg) route as line S19 since 14 December 2014. Siegburg/Bonn and Hennef (Sieg) are normally served by the S12.