The project, spanning a total of 120 kilometers (68 of which will be newly constructed) with 40 stations (23 new), has an estimated investment of 5.2 billion euros. The most optimistic timeline aims for the new train's completion by 2041, with a phased rollout allowing for independent operation of different sections. The first phase, connecting Granollers and Terrassa via Sabadell, is the only one with guaranteed funding through the 2026-2030 Cercanías Plan.

The Government describes the forecasts as "realistic" regarding the timeline. However, funding for the new network still presents uncertainties. Currently, only 665 million euros are secured for the section between Santa Perpètua de Mogoda and Sabadell, within the Granollers-Terrassa phase. To cover the remaining necessary funds, discussions have begun with the State to explore new financing avenues, which could be finalized "in the coming days".

The project will be built in sections, allowing for progressive implementation. The first phase will connect Granollers and Terrassa with approximately 32 kilometers and fifteen stations (five new), with completion projected for 2034 for the Santa Perpètua-Barberà section to Sabadell Nord. This phase includes significant improvements to the existing network and a "phase zero" with new interchanges in Rubí, Sant Cugat, and Sabadell.

The second phase will link Mataró with Granollers (Maresme with Vallès Oriental) by 2037, featuring 23 km of new tracks and six stations, with an investment of 1.45 billion euros. The third phase will connect Terrassa with Vilafranca del Penedès in 2040, including a new stretch between Terrassa and Martorell and six stations, utilizing the R4 south route from Martorell, with an investment of 1.15 billion euros. Finally, the last phase (2041) will complete the ring with 29 km of tracks and six more stations between Vilafranca del Penedès and Vilanova i la Geltrú, costing 1.4 billion euros.

The objective of this infrastructure is to enhance public transport connections around Barcelona, breaking the radial model and creating a networked system. The Minister of Territory, Sílvia Paneque, argues that this model offers "more complete mobility" and highlights the current period of investment in Catalonia. The Government emphasizes overcoming a long-standing "deficit" in railway investments that bring "competitiveness" to the benefiting regions. The orbital line's top speed will be 120 km/h, with an average speed estimated at 60 km/h, allowing journeys like Martorell-Granollers in approximately 45 minutes.