20.4 km, do you know what that number is?

20.4 km is the total length of the route, of the future T12 tram-train, from Evry-Courcouronnes to Massy Palaiseau.

After about two years of work, the laying of the rails was completed this month. While the T12 tram-train will replace the RER C from Massy to Epinay-sur-Orge over 10km, new tracks have been created to the south.

In total, 10.4 km of new tracks have been built, to allow the T12 tram-train to continue its journey in the city in order to serve the cities of Morsang-sur-Orge, Viry-Châtillon, Grigny, Ris-Orangis and Evry-Courcouronnes.

The rails are laid on concrete sleepers, a solution known for its robustness and longevity. Once wedged and aligned under the control of a surveyor, they are welded to each other by a process that guarantees good resistance to overloads. Concrete is then poured for the real estate. Finally, the whole thing is covered with sedum, a plant cover that is easy to maintain and requires little watering.

The T12 tram-train will run like a train between the Massy-Palaiseau and Petit Vaux stations and like a conventional tram in the urban sector between Épinay-sur-Orge and Évry-Courcouronnes. The line will then be equipped with specific trains, capable of running on both types of rails and under two different driving modes.