Connection between Gare du Nord and Gare de l'Est.
Two things are planned.
Improving the connection at street level between the two stations and the construction of a tunnel
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1 - Improving pedestrian travel
This first aspect is based on rue d'Alsace and rue de Dunkirk, with work on pedestrian traffic and improvement of signage.
Work on the surrounding of the Magenta station will also be realized. Its square could be redeveloped, there are studies on a building SNCF located nearby on 50 rue d'Alsace. This sector of convergence between stations could make possible to open Gare de l'Est with Gare du Nord.
2 - Creating an underground link
The second major point of the project is to connect two tunnels: the Château-Landon tunnel, which crosses all the platforms of Gare de l'Est, and the tunnel under the Magenta station to the platforms of Gare du Nord.
Château-Landon tunnel now allows access via stairs to the platforms of the Gare de l'Est. It would be renovated, and elevators would be built, as far as possible, to access certain platforms of the Gare de l'Est from the tunnel for people with reduced mobility.
By digging an additional 60 meters of tunnel under Rue La Fayette, a large subterranean link to Gare du Nord would be built.
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http://www.nouvelle-liaison-gare-nor...pes-du-projet/