rer

This page is about the Paris commuter rail. In biology, 'RER' is the abbreviation for rough endoplasmic reticulum.

RER (French: pronounced "air-euh-air") is an urban public transportation network in and around the Paris region. For the concept of suburban railway lines in tunnels in the centre of a city, see regional express network. Nevertheless, the acronym RER is commonly used to describe the network that is currently being planned for the Brussels region, just as the major cities of Switzerland (S-Bahn in German). The RER is composed of lines dating from the 19th century, such as the Ligne de Sceaux or the Paris-St Germain-en-Laye line (the first railway in France) and the Bastille's railway, which is from a line dating to the 1960s (La Dfense line) and tunnels underneath Paris that were put into service starting in 1977. The Parisian RER is peculiar in the sense that certain segments are operated by the RATP and others by the SNCF. The practice of direct trains going from one operator to another is called interconnection.

History

The Parisian RER is composed (in 2003) of five lines: A, B, C, D, and E. In 2003, the only Parisian SNCF station to not be directly connected to the RER is Gare Montparnasse. The TGV trains that arrive there are interconnected further upstream at Massy-Palaiseau. In fact, the whole system is built out of SNCF lines, but in the first phase, the government transferred the right to operate the lines from the SNCF to the RATP (Sceaux line, Saint-Germain-en-Laye line, Boissy-Saint-Lger line), then, in a second phase, the SNCF kept the right to operate its own lines. Only the central portion of line A (La Dfense-Vincennes) and line B (Gare du Nord-Chtelet-Denfert-Rochereau) were constructed by the RATP. This explains why the RER trains drive on the left, like SNCF trains (except in Alsace and in Moselle), contrary to the Paris Metro where trains drive on the right.

Line A

After many years of planning, construction began on the network on July 6, 1961 with line A. The first segments to be built new involved the extension of the old Saint-Germain-en-Laye line, re-electrified using an overhead system (it had originally been electrified using third rail) on a new alignment from Nanterre through La Dfense and the new stations of Auber (at the time of its construction the largest underground station in the world) and Chtelet-Les-Halles in the heart of Paris. The extension to Gare de Lyon joined up the existing Vincennes line (Bastille to Boissy-Saint-Lger), completing the original line A. A branch of line A from Vincennes to Marne-la-Valle was built new. This was subsequently extended to Disneyland Resort Paris.

Line B

Line B resulted from connecting the Luxembourg terminus of the Ligne de Sceaux with the Gare du Nord main line railway terminus through Chtelet-Les-Halles.

Line C

Line C was created by connecting the Gare d'Orsay railway terminus (the present-day Muse d'Orsay) with the Invalides terminus of the Rive Gauche line to Versailles along the banks of the Seine.

Line D

Line D connected the Gare du Nord with the Gare de Lyon via Chtelet-Les-Halles.

Line E

Finally, the construction of line E in 1998 between the termini of Gare Saint-Lazare and Gare de l'Est left the Gare Montparnasse the only main line terminus in Paris not directly connected to the RER system, the TGV line out of Montparnasse being served by the RER through the suburban hub of Massy Palaiseau (see Ligne de Sceaux).