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RER B
RER B train atAéroport Charles de Gaulle 2 TGV
Overview
Termini	Aéroport Charles de Gaulle 2 TGV (B3),Mitry–Claye (B5) Robinson (B2),Saint-Rémy-lès-Chevreuse (B4)
Connecting lines
Stations	47
Service
Type	Rapid transit/commuter rail
System	Réseau Express Régional
Operator(s)	RATP/SNCF
Rolling stock	MI 79,MI 84
Ridership	165 million journeys per annum (2004)
History
Opened	8 December 1977; 47 years ago (1977-12-08) (last extension in 1994; 31 years ago (1994))
Technical
Line length	80 km (50 mi)
Track gauge	1,435 mm (4 ft 8+1⁄2 in)standard gauge
Electrification	Overhead line:    25 kV 50 Hz AC    1,500 V DC
Route map Show geographically accurate map Legend proposed extension Rouvres  Dammartin–Juilly –Saint-Mard   Thieux–Nantouillet  Compans  Aéroport CDG 2 TGV B3   B5 Mitry–Claye  Aéroport CDG 1 Villeparisis – Mitry-le-Neuf Aérofret Parc des Expositions Vert-Galant Villepinte Sevran – Livry *  *Sevran – Beaudottes    Aulnay-sous-Bois Le Blanc-Mesnil Drancy   *  Le Bourget La Courneuve–Aubervilliers La Plaine–Stade de France ↑25 kV AC ↓1.5 kV DC        Gare du Nord ( Magenta Gare de l'Est )         Châtelet–Les Halles Seine     Saint-Michel–Notre-Dame Luxembourg Port-Royal    Denfert-Rochereau   Cité Universitaire Gentilly Laplace  * Arcueil–Cachan Bagneux Bourg-la-Reine Sceaux Parc de Sceaux Fontenay-aux-Roses La Croix de Berny   Tvm  Robinson B2  Antony Fontaine-Michalon Les Baconnets   Massy–Verrières   *   Massy–Palaiseau Palaiseau Palaiseau–Villebon Lozère Le Guichet Yvette Orsay-Ville Bures-sur-Yvette La Hacquinière Gif-sur-Yvette Courcelle-sur-Yvette  B4 Saint-Rémy-lès-Chevreuse All stations are accessible * Under construction This diagram: view talk edit Show diagram map

RER B is one of the five lines in theRéseau Express Régional (English: Regional Express Network), a hybridcommuter rail andrapid transit system servingParis, France and itsÎle-de-France suburbs. The 80-kilometre (50 mi) RER B line crosses the region from north to south, with all trains serving a group of stations in central Paris, before branching out towards the ends of the line.

The line opened in stages starting in December 1977 by connecting two existing suburban commuter rail lines with a new tunnel under Paris: theChemin de Fer du Nord to the north (which formerly terminated atGare du Nord) and theLigne de Sceaux to the south (which formerly terminated atLuxembourg station).

The RER B, along with the rest of the RER network, has had a significant social impact on Paris and the surrounding region by speeding up trips across central Paris, by making far fewer stops than theParis Métro and by bringing far-flung suburbs within easy reach of the city centre. The line has far exceeded all traffic expectations, with passengers taking 165 million journeys per year in 2004. That makes the RER B the second busiest single rail line in Europe (afterRER A).

The line faces capacity challenges as a result of sharing a tunnel withRER D trains betweenChâtelet–Les Halles and Gare du Nord.

The RER B opened in stages starting in December 1977 by connecting two existing suburban commuter rail lines with a new tunnel under Paris: theChemin de Fer du Nord to the north (which formerly terminated atGare du Nord) and theLigne de Sceaux to the south (which formerly terminated atLuxembourg station).

• June 1846: TheLigne de Sceaux fromMassy toDenfert-Rochereau opens to the public.
• 1862: TheChemin de Fer du Nord line from Paris toSoissons viaMitry-Claye is opened.
• 1895: The Ligne de Sceaux is extended from Denfert-Rochereau toLuxembourg.
• 1937: TheCMP (the operator of theParis Métro and predecessor of today'sRATP) purchases theLigne de Sceaux, planning to integrate it into a future regional metro network, now known as theRéseau Express Régional (RER).
• May 1976: A new 13.5 km (8.4 mi) long branch fromAulnay-sous-Bois toParis-Charles de Gaulle Airport (terminal 1) is opened, linking the airport with Paris.
• December 1977: The Ligne de Sceaux is extended north 2 km (1.2 mi) from Luxembourg station toChâtelet-les Halles station and becomes theRER B.
• December 1981: The RER B is extended north 2.5 km (1.6 mi) fromChâtelet-les Halles station toGare du Nord connecting with trains to Mitry-Claye and the airport. Because the lines north of Gare du Nord used a different electrification system (1.5 kV DC to the south, 25 kV AC to the north), passengers need to make across-platform transfer between trains on the north and south lines.
• January 1983: A new station,Parc-des-Expositions, opens betweenVillepinte andRoissy.
• June 1983: Improvements anddual-voltage equipment allow trains to begin traveling through Gare du Nord and across the entire length of the line.
• February 1988: A new station,St-Michel – Notre-Dame opens between Luxembourg and Châtelet to offer a quick connection withRER C andParis Métro Line 10 atCluny – La Sorbonne, a station which had been closed sinceWorld War II and was entirely renovated.
• October 1991:OrlyVAL line opens, connectingAntony station withOrly Airport.
• November 1994: The line is extended 1 km (0.62 mi) north toAéroport Charles de Gaulle 2 – TGV.
• January 1998: A new station,La Plaine–Stade de France, opens near theStade de France in time for the1998 FIFA World Cup.

The RER B Line has two service patterns:

• Off-peak hours on weekdays, Saturdays and Sundays
• Rush hour during the week (and special events such as matches at the Stade de France or construction work)

In any case, the stations from Cité Universitaire to Paris Gare du Nord are served by every single train.

In 2021, theoff-peak service is made up of 3 missions per 1 / 4H:

To the south:

• Mission K, (KALI, KARE, etc.) for Massy–Palaiseau (Massy)
  • Non-stop train between CDG and Paris, then local train from Paris to Massy

• Mission S, (SVAN, SOLO, etc.) for Robinson
  • Local train on the entire line between Mitry—Claye and Robinson

• Mission P, (PEPE, PILE, etc.) for St Remy-lès-Chevreuse
  • Local train between CDG and Paris, rapid/semi-direct train between Paris and Massy–Palaiseau, then local train to St Remy

To the north:

• Mission E, (EKLI, ELAN, etc.) for CDG2
  • Local train in the south between Massy and Paris, then non-stop/direct train between Paris and CDG2

• Mission E, (EFLA, ERGE, etc.) for CDG2
  • Local train between St Remy and Massy, rapid/semi-direct train between Massy and Paris, then local train from Paris to CDG

• Mission I, (IBIS, IMRE, etc.) for Mitry-Mory
  • Local train on the whole line

Rush hour is between 07:00 and 09:45 in the morning and between 16:00 and 20:00 in the afternoon.

In 2021 therush hour service is made up of 4 missions per 1 / 4H:

In the northern section after Paris Gare du Nord, all trains are local trains.

To the south:

• Mission K, (KALI, KARE, etc ...) for Massy–Palaiseau (Massy)
  • Rapid train from Paris to Massy

• Mission L, (LUNE, LEVE, etc ...) for Orsay
  • Rapid train from Paris to Massy then local train between Massy and Orsay

• Mission S, (SVAN, SOLO, etc ...) for Robinson
  • Local train until Robinson

• Mission P, (PEPE, PILE, etc ...) for St Remy-lès-Chevreuse
  • Semi-direct train between Paris and Massy–Palaiseau, non-stop train between Massy and Orsay, then local train between Orsay and St Remy

To the north:

In the northern section after Paris Gare du Nord, all trains are local trains.

• 2 Mission E to Roissy
• 2 Mission I to Mitry Mory

Some infrequent missions can be seen such as missions J to Denfert Rochereau in the evening.

RER B mission codes are made up of four letters followed by two numbers. The first letter always indicates the destination.

RER B is operated by 117 sets of theMI 79 series and 31 sets of theMI 84 series. These are to be replaced from 2025 by the MI 20 series.^[1]

Past fleet include theMS 61, which operated on the line from 29 June 1967 to 28 February 1983, and theClass Z 23000, which operated from 16 November 1937 to 27 February 1987.

As part of theGrand Paris public works programme, the creation of a newinfill station called "Aérofret" betweenParc des Expositions station to the south andAéroport Charles de Gaulle 1 station to the north was proposed. The new station would be located adjacent to and serve the Aéroville mall as well as planned development on the western side of the freight areas on the western side ofCharles de Gaulle Airport. It is slated to open by 2025 along with the planned developments in the area.^[2]

Already proposed in the 1994 Schéma directeur de la région Île-de-France (Île-de-France regional development plan, SDRIF), but without any concrete plans ten years later,^[3] the project to extend RER B northeast fromMitry–Claye station to theDammartin-en-Goële area, serving intermediate stations atCompans andThieux-Nantouillet, is proposed in Phase 3 (horizon 2021-2027) of the revised SDRIF, adopted by deliberation of theRegional Council of Île-de-France on September 25, 2008.^[4] It would also involve the creation of a new terminus station located in the neighbouring commune ofRouvres, some 3.5 km (2.2 mi) north of the currentDammartin Juilly Saint-Mard station nearSaint-Mard, which is old and unsuitable for such a project.^[5] The project is now expected to be completed around 2030.

• List of stations of the Paris Métro
• List of stations of the Paris RER

• RATP official websiteArchived 25 December 2008 at theWayback Machine(in French)
• RATP website in English

• Réseau Express Régional
• Railway lines opened in 1977
• 1977 establishments in France

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