The RER (Réseau Express Régional) is a network of commuter trains connected to the metro system serving Paris and its surrounding areas. For example, you can take the RER to Charles de Gaulle and Orly airports, Disneyland Paris, Versailles and other suburban destinations. The RER trains also stop at SNCF railway stations. Metro tickets can be used on RER trains withing the city limits; for destinations outside of Paris you'll have to pay more for a ticket. With the RER you'll travel faster across Paris as there are fewer stops within the city. The RER has only 5 lines lettered A through E.

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