Rhône Express Régional

The Geneva RER or Rhône Express Regional is a commuter railway service which runs between Geneva Cornavin Station, Switzerland (where it mostly uses the dedicated Platform 5) and La Plaine (Swiss terminus) and Bellegarde-sur-Valserine in France. It forms part of the Lyon-Geneva Railway. It is probably not a coincidence that the initials correspond to the Paris suburban railway commuter network RER.

This line used to be electrified at 1500V DC and signalled to SNCF standards from the border to both Geneva's central passenger station and La Praille goods depot.

Prior to the introduction of the "RER" brand in 1995 the Geneva - La-Plaine service was operated by two notoriously unreliable BDe 4/4 II railcars.

Initially, service was operated by five specially built two coach articulated railcars of class Bem550. These were built by Vevey Technologies (formerly Ateliers de Constructions Mécaniques de Vevey (ACMV)) with electrical equipment by Asea Brown Boveri in 1994. They ran under 1.5kV DC wires, but were equipped with a diesel engine to enable them to reach the workshops.

When the service frequency was expanded, some trains composed of RIO carriages hauled by BB25500 series locos. This rather antiquated rolling stock was replaced progressively by Stadler FLIRT RABe 524 EMUs.

From December 2010, to June 2014, Geneva - la Plaine services were operated by three Stadler FLIRT RABe 524 EMUs, which were not certified to run beyond la Plaine, while Geneva-Bellegarde services were operated by the Bem550s. The RABe 524 were taken temporarily from the Ticino railway network as they can also run on 1.5 kV DC. These sets went back to Ticino when the Genève-La Plaine line was re-electrified with 25 kV AC as they cannot use that voltage, to be replaced by RABe 522 EMUs.

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