[3] The system consists of 17 service lines chiefly centred in the Barcelona area, serving a total of 203 stations throughout Catalonia, with an average number of 1,000 trains running on it every day.

[4] Most part of the system is the precursor of several commuter and regional lines running on the Iberian gauge mainline network in Catalonia, which were formerly under the administration of the Spanish government.

[6] In 2014, two new commuter rail services in Camp de Tarragona and the Girona area were created as part of the system on 20 and 24 March, respectively.

[7][8] Rodalies de Catalunya, especially its Barcelona commuter rail service, has been criticised for its high number of incidents, normally resulting in delays, though some minor accidents involving injuries have also occurred.

Excluding the Vic–Latour-de-Carol portion, it runs on 467 kilometres (290 mi) of railway lines and has 109 stations in 77 municipalities, accounting for a population of 4.7 million.

Lines R2, R2 Nord and, partially, R2 Sud use the Aragó Tunnel, comprising Passeig de Gràcia and El Clot-Aragó stations.

[14] Renfe created the Cercanías Barcelona/Rodalia Barcelona branding in 1979 with the aim of absorbing the traffic of passengers who enter and leave the Catalan capital every day.

In 1984 Renfe was in a critical economic situation due to the high number of deficient lines, which is why it decided to close many of them, part of which were saved by the Autonomous Communities.

[16] However, due to construction works near Barcelona Sant Andreu Comtal railway station, a "temporary" restructuring of lines R2 and R10 was implemented on 31 January 2009 (2009-01-31); the R10 was suspended and the R2 was divided into three different lines—R2, R2 Nord ("North") and R2 Sud ("South").

Before the restructuring, former line R7 ran from L'Hospitalet de Llobregat to Martorell via the Meridiana Tunnel in Barcelona's city centre and Rubí.

With the rerouting, it was shortened and started to run as a shuttle line between Cerdanyola Universitat and Barcelona Sant Andreu Arenal stations.

Line RT1 actually serves as a reinforcement for regional services between Tarragona and Reus with 9 additional trains in each direction, allowing a service pattern of approximately 30 minutes during rush hour and lower to one hour during off-peak time between the two cities, combining all lines.

[7] Although line RT2 initially ran only between L'Arboç and Cambrils, from 20 June 2014 (2014-06-20) on, some trains travel further west to L'Hospitalet de l'Infant stopping at Mont-roig del Camp.

It consists of a single 44-station line named RG1 (letter 'G' referring to Girona), which directly links the Alt Empordà, Gironès, Selva and Maresme areas.

However, from 20 June 2014 (2014-06-20) on, some trains travel further north towards Portbou and additional weekend services are offered during the summer season.

Specifically, the following types of train services are present in the system's division for regional lines: In the Barcelona area, Rodalies de Catalunya participates in the Autoritat del Transport Metropolità's integrated fare system,[46] allowing the use of standardized zone-based tickets with transfers to other operators such as the Barcelona Metro.

[48] The most common class of EMU in the network, serving as the backbone of most commuter lines and providing some regional service, such as on R3.

[53] In 2021, the Spanish Ministry of Transport announced the purchase of a large order of new EMUs to renovate and expand the commuter rail fleet operated by Renfe, mainly in the networks of Barcelona and Madrid.

It was confirmed that 72 Renfe Class 452 [es] trains would bolster the fleet of Rodalies de Catalunya, starting trial operations in 2025 to enter service in 2026.

[57][58] Another derailment on the same line occurred on 8 February 2019 between Sant Vicenç de Castellet and Manresa, killing the driver and injuring several other people.