Network modernisation

On course for the Metro line 4 extension

From noon on 13 January 2022, you’ll be able to travel to the Bagneux – Lucie Aubrac station on line 4!

The metro line 4 extension will be put into service at noon on 13 January 2022, thereby connecting the Mairie de Montrouge station with the new Bagneux – Lucie Aubrac terminus. 37,000 additional passengers will use line 4 each day at the Barbara and Bagneux – Lucie Aubrac stations.

Ligne 4

The aim of the extension is to increase the density of the rail service to the inner suburbs. The extended metro line 4 sits between metro line 13 to the west and RER line B to the east. Connected to the future orbital metro line 15, it will strengthen the Île-de-France rail network. The idea is to fully support the urban development of the municipalities of Bagneux and Montrouge, notably the revitalization operations carried out as part of the Victor Hugo eco-neighborhood ZAC (mixed development zone) in Bagneux.

Prolongement de la ligne 4 : les coulisses de l’inauguration | RATP

Key figure

30 minutes
This is the journey time between Bagneux - Lucie Aubrac and Châtelet - Les Halles.

An explosive campaign to announce the metro line 4 extension

As the opening of the two new stations approaches, a communication campaign provides a humorous recap of the new travel possibilities that the line extension will offer.

campagne de communication pour le prolongement de la ligne 4


L’architecture des deux nouvelles stations

Sound announcement

Découvrez les annonces sonores des deux nouvelles stations :


Bagneux - Lucie Aubrac

Prolongement de la ligne 4 : les noms des stations

Les œuvres de C215, en hommage à Lucie Aubrac

Technical challenge

The extension corresponds to six years of construction works that included a 1.8 km tunnel extension and the construction of 2 new stations in a dense urban environment, as well as the construction of a new 1,500 m2 train repair center. A true technical challenge met by the teams mobilized.

Practical information