The project flies over a railway slab. The whole difficulty lies in installing a building that has no foundation.
The building sits on three massive beams fixed by the SNCF to span the train tracks. Three spans of posts, like long and delicate paws of flamingos, rest exactly on the existing beams.

A living box is placed on top of these feet. Between these intertwine a succession of events to bring the Avenue de France to life.

The project is designed as a stack of programs: Shops on the ground floor, an aerial sports platform on the first floor, an activity room on the second floor, and seven identical floors of rooms with a roof garden.
The interstitial void between the programs on the ground floor and the upper floors acts as a captivating signal.
The enhanced underside creates an attraction visible from all points of the street.
The building is designed for the pedestrian. Who sees the bikes as they climb the ramp to their parking lot on the first floor. Who also sees sportsmen come alive on the same floor.