Its IATA code is QKL. Long-distance services Cologne Hauptbahnhof is the hub of many Intercity Express and Intercity lines, mostly serving Cologne every hour or every two hours: Various high-speed services connect most cities in Germany as well as several neighbouring countries in a few hours. Thalys high-speed trains run from Cologne to Paris via Aachen, Liege and Brussels. An international Intercity Express service also operates every two hours during the day on the Brussels–Liege—Aachen–Cologne line, continuing to Frankfurt. With a combined 403 scheduled long-distance arrivals and departures each day at Cologne in the summer timetable of 1989, it was the most important node in the network of Deutsche Bundesbahn. With 383 scheduled long-distance arrivals and departures, in Deutsche Bahn's timetable of summer 1996, it was the second most important node (after Hannover Hauptbahnhof). Regional services Cologne Hauptbahnhof is also a hub for numerous Regional-Express and Regionalbahn services, mostly serving the station in Cologne every half-hour or hour, but sometime only every two hours: S-Bahn trains Köln Hauptbahnhof is integrated in the Rhein-Sieg S-Bahn network. From Monday to Friday S-Bahn trains run at 20-minute intervals during the day and at other times usually every 30 minutes. It is also served on working days by the S19 service between Düren and Au (Sieg), running hourly but substituting for an S13 service. Northwest of the Cologne Hauptbahnhof S-Bahn station is the Köln Hansaring S-Bahn station and to the east is the Köln Messe/Deutz S-Bahn station. All S-Bahn services serving the station, use these two stations. Local services Below Cologne Hauptbahnhof there are two stations of the Cologne Stadtbahn. Stadtbahn stations Dom/Hauptbahnhof and Breslauer Platz/Hauptbahnhof are on the same tunnel that runs under the main station making a turn of 120 degrees. The former one is located below the southern end, next to the cathedral, the latter at the northern end where it connects to the bus station. Breslauer Platz/Hauptbahnhof station was relocated and completely redesigned up December 2011. Line 5 has been rerouted from Dom/Hauptbahnhof to Rathaus station to connect with the first open part of the north-south Stadtbahn tunnel, which is currently under construction. One year later line 5 was lengthened one station from Rathaus to Heumarkt. Formerly, all trains stopped at Dom/Hbf and Breslauer Platz/Hbf, but, as the junction for the new line will be between these stations, line 5 trains only stop at Dom/Hbf, and line 16 trains will