Paris's RER (EHR-uh-EHR, Réseau Express Régionale) is the network of five suburban train lines that pass right through the city center, connecting outlying towns in the Île-de-France with the capital.

RER Within Paris

Although several RER lines have stations adjoining Métro stations, and you could use RER trains to go from one part of Paris's city center to another, it's usually faster and easier to use Paris's superb Métro system or city buses to move about in the city itself, and use the RER for trips to the suburbs, outskirts and airports.

For example, Métro trains usually arrive and depart every few minutes, whereas during off-peak commuting times, RER trains may be 30 minutes apart.

Airports & Train Stations

RER lines connect Paris with its two busiest airports (Roissy-Charles de Gaulle, and Orly) and important intercity train stations including Gare du Nord, Gare de Lyon, and Gare d'Austerlitz. For details on taking trains to and from the airports, see these pages:

—Aéroport Charles de Gaulle Transportation

—Aéroport Orly Transportation

The 5 RER Train Lines

The RER's five lines are lettered/numbered and color-coded:

A - Red (A1, A2, A3, A4, A5)
B - Blue (B1, B2, B3, B4, B5)
C - Yellow (C1, C2, C3, C4, C5, C6, C7, C8)
D - Green (D1, D2, D3, D4)
E - Purple (E1, E2, E4)

The letter designates the line, the number designates the branch of the line, as each line divides into branches at one or both ends.

(Note: there are also many SNCF Transiien train lines with letters. More...)

RER vs. Métro

The RER and Métro systems have these differences:

1. Fares on the RER can be higher than those on the Métro. A Métro ticket may be valid for a short RER journey in the center of Paris, but you may incur a fine for underpaying if you use a Métro ticket for a longer journey. You should assume that you'll need a separate RER ticket for any RER journey beyond a few stations in central Paris.

2. You should hold onto your ticket until the end of your journey on both the Métro and the RER (to prove that you paid to ride), but on the RER you must actually use your ticket to exit the station. If you don't have your ticket, you'll have to pay a fine...or stay in the station indefinitely.

	Look for the bike logo

3. Trains on the RER are larger, heavier, longer and less frequent than Métro trains.

Many RER train cars have bicycle compartments where you can put your bike or large luggage. Look for the bike logo to discover where to put your bicycle.

4. Finding the train you want is different on the RER. See Riding the RER for details. More...

RATP Apps

RER trains are included in the routes planned by the highly useful smartphone apps offered by RATP, for free, for Apple iOS, Google Android, and Amazon. See the appropriate app store for more.

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Riding RER Trains Paris Métro Transilien (Île de France) Trains Paris Train Stations (SNCF) Paris City Buses Paris Airports CDG Airport Transport Orly Airport Transport Paris Transport