Paris–Orléans–Limoges–Toulouse and Clermont–Paris: Two key rail corridors entering a new phase of development

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These lines, both key routes for the national network and for the regions they serve, have been undergoing modernisation and upgrades since 2018. Work accelerated sharply in early 2024. By 2027, close to €3 billion will have been invested jointly with the French government to deliver lasting improvements in infrastructure performance, benefitting all users of these lines.

Rail lines at the heart of the regions

The Paris–Orléans–Limoges–Toulouse (POLT) corridor spans more than 700 km of track, linking Île-de-France, Centre-Val de Loire, Nouvelle-Aquitaine and Occitanie, and serving 2.6 million Intercités passengers each year. The Clermont–Paris line covers more than 420 km of track, connecting Île-de-France with the Massif Central and carrying 1.9 million Intercités passengers annually. Through the modernisation of these two strategic corridors, we are committed to delivering faster, more reliable and more accessible journeys which meet the needs of daily commuters, tourists and freight operators alike.

Logos des lignes POLT et Paris-Clermont

Unprecedented investment

Both lines are still equipped with a mix of ageing technical installations and therefore require extensive modernisation to significantly enhance mobility services.

On the Paris–Orléans–Limoges–Toulouse line

Nearly €2 billion is being invested to modernise and upgrade the line:

  • Over €1.6 billion from SNCF Réseau between 2018 and 2026 to renew the tracks
  • €260 million from the French government to modernise the power supply and increase train speeds around Argenton-sur-Creuse

On the Clermont–Paris line

Nearly €1 billion is being invested in infrastructure upgrades:

  • €800 million from SNCF Réseau between 2018 and 2026 to renew the line
  • €130 million in modernisation works funded by the French government (two-thirds) and the Auvergne–Rhône-Alpes Region (one-third)

Why carry out works?

This work is essential. On the POLT line, some of the catenary masts date back to the Second World War. By 2030, half of the catenary masts on the line will have been replaced across more than 350 km. On the Clermont–Paris line, upgrades to the power supply are needed to accommodate new rolling stock from various operators (TER Bourgogne, TER Centre, RER D, line R and Intercités Clermont–Paris).

Keeping trains running during the works

Since 2018, work has been carried out at a steady pace. However, we are doing everything possible—in coordination with passenger (Intercités, TER) and freight operators—to maintain rail services throughout the construction period.

Major works underway

The work being carried out on both lines is broadly similar in nature:

  • Power supply upgrades

    Reinforcements across the entire POLT line and the northern half of the Clermont–Paris line, with the southern section already electrified more recently.

  • Increased speeds

    Up to 160 km/h on 55 km of track around Argenton-sur-Creuse (POLT line), and on seven separate sections between Clermont and Paris.

  • Platform height upgrades

    To allow level boarding, including for passengers with reduced mobility.

  • Replacement of rails, overhead lines and switches

    Designed to reduce delays, with upgrades continuing beyond 2026 to ensure the long-term reliability of the track and technical systems.

  • Environmental protection

    Vegetation management and wildlife-friendly infrastructure, with a 50% increase in the associated budget between 2020 and 2024.

  • Safety and smoother operations

    Modernisation of signal boxes and preventive maintenance of trackside components using remote monitoring and centralised supervision.

A long-term improvement in service quality

All of the work being carried out on the rail network is designed to ensure infrastructure quality and safety for decades to come. It will also significantly improve the transport offering on both lines, with:

  • a journey time reduction of around 10 minutes between Paris and Clermont-Ferrand, and 15 to 20 minutes between Paris, Limoges and Toulouse
  • improved train punctuality and fewer delays in the event of an incident 
  • one additional daily return service, bringing the total to 9 return trips per day on the Clermont–Paris line and 11 on the POLT line
  • a high level of on-board comfort thanks to the upgraded infrastructure
quai modernisé de la gare de Vierzon

Ready for the Oxygène trains!

The French State, as the Organising Authority for Trains d’Équilibre du Territoire, is introducing a new service offering on both lines at the same time. Over the course of 2027, 28 new Intercités trainsets, known as “Oxygène”, will be gradually brought into service, with the aim of fully replacing the current Corail trains by December. These new trains will offer greater accessibility and comfort, be better suited to passenger needs and help reduce journey times.

Visuel extérieur de la nouvelle rame Oxygène

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