S2 (RER Vaud)
The S2 is a railway service of RER Vaud that provides hourly service between and in the Swiss canton of Vaud. A limited number of trains continue to . Swiss Federal Railways, the national railway company of Switzerland, operates the service. Operations. The S2 operates every hour between and , using the western end of the Simplon line. The rush-hour-only S22 provides additional service between Vallorbe and , with additional through service to . The S2 is paired with the S5 between Lausanne and Aigle, providing half-hourly service. The S2 makes a limited number of stops over this  section, while the S5 makes all local stops. Most S2 trains begin and terminate at Aigle, but there is limited service to . History. The S2 was one of the six original lines of the RER Vaud, then called the Vaud Express Network (, REV), when that system was established in December 2004. It ran hourly between Vallorbe and , on the Lausanne–Bern line. With the December 2015 timetable change, the S2's eastern terminus shifted to , on the Simplon line. The eastern terminus moved further to Aigle in December 2020.