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R7 services started operating in 2005, initially running between Martorell and L'Hospitalet de Llobregat stations, via the Vallès Occidental region. The line used most part of the Castellbisbal–Mollet-Sant Fost railway, and the entire Meridiana Tunnel through central Barcelona. It became the first passenger service to use the Castellbisbal–Mollet-Sant Fost railway, originally designed to serve as Barcelona's rail freight bypass. In 2011, the R7 was shortened, so that it began to operate in its current configuration between Sant Andreu Arenal and Cerdanyola Universitat stations. Most part of its original route was then taken over by the R8, which came into service the same year, running between Martorell and Granollers. In the long-term future, it is projected that the R7 will be extended southwards to Barcelona–El Prat Airport, using the Meridiana Tunnel.
List of stations
The following table lists the name of each station served by line R7 in order from south to north; the station's service pattern offered by R7 trains; the transfers to other Rodalies de Catalunya lines, including both commuter and regional rail services; remarkable transfers to other transport systems; the municipality in which each station is located; and the fare zone each station belongs to according to the Autoritat del Transport Metropolità (ATM Àrea de Barcelona) fare-integrated public transport system and Rodalies de Catalunya's own fare zone system for Barcelona commuter rail service lines.
Recio, Alfons (31 December 2005). "Ferrocarril de rodalies C-7 El Papiol - Mollet" [Commuter rail line C-7 El Papiol - Mollet]. Territori (in Catalan). Societat Catalana d'Ordenació del Territori. Retrieved 4 October 2015.
Arenós, Paloma (17 May 2005). "El tren deseado" [The wished train] (PDF). La Vanguardia (in Spanish). Sant Cugat del Vallès. Vivir section (p. 1). Retrieved 19 September 2015.
Cabañas, Néstor (31 December 2011). "Ferrocarril de rodalies Martorell - Granollers" [Martorell - Granollers commuter rail]. Territori (in Catalan). Societat Catalana d'Ordenació del Territori. Retrieved 4 October 2015.
Julià Sort, Jordi (October 2013). Sagrera i la xarxa ferroviària de Barcelona [Sagrera and Barcelona's railway system] (in Catalan). Barcelona: Viena Edicions. p. 144–145. ISBN978-84-8330-740-3.
R7 Rodalies (rod7cat) on Twitter. Official Twitter account by Rodalies de Catalunya for the R7 with service status updates (tweets usually published only in Catalan)