How will the location of the annex structure between the city centre and the station be chosen?

For a single-tube tunnel, the regulations require emergency access to the tunnel every 800m maximum, via a station or an ancillary structure. In the present case, the location of the ancillary structure implies having previously defined the location of the station located in the counter-city and the configuration of the terminus at the station. Once these elements have been stabilised, it is possible to define a precise route and propose sites for the installation of the ancillary structure. The location of the latter will therefore be specified in the rest of the studies.

It should be noted that the ancillary structure can be slightly offset from the route and connect to the tramway tunnel via a connecting tunnel, while taking care to limit the additional access time for emergency services.