The RER lines (Réseau Express Régional or Regional Express Network) are different from other train lines because they do not terminate in Paris. They cross the capital underground, so that passengers can get from one side of the region to the other on the same line.


  • 5RER lines
  • 600kms of tracks throughout the region
  • 249stations
  • 2.7million daily passengers
  • +20%increase in ridership in the last 10 years

At your service

  • Presentation

    The Ile-de-France Mobilités network has five RER lines crisscrossing the region.
  • Improvements and projects

    Find out about infrastructure modernisation and line extensions and all the ongoing work and projects that will bring you tomorrow’s RER!