what is rer in paris

The Réseau Express Régional (RER) is a hybrid commuter rail and rapid transit system serving Paris and its suburbs. It acts as a combined city-center underground rail system and suburbs-to-city-center commuter rail. In the city center, it acts as a faster counterpart of the Paris Métro, having fewer stops. The RER provides better coverage of Paris suburbs and typically operates at higher speeds and with greater distances between stations. The RER has five train lines, designated A through E, with many branch lines. The RER system has its hubs in Paris, but also runs a long way outside the city, serving suburbs like Versailles, Saint-Germain-en-Laye, Charles de Gaulle Airport, and even Disneyland Paris. The RER also complements the Paris Metro, giving Parisians and tourists a larger transport network in the center of Paris. The RER takes the same tickets and the same passes as the Metro within central Paris.