This project is an urban development strategy. It is not per se an architectural project. To be more accurate, architecture is used as a device to generate a territory with its specific landscape. Inside this topography not only is a river flowing, but also a park-garden which preserves the existing trees. We want this new district to develop harmonious relationships between nature and architecture. This long green space runs through the site and joins the two entrance crossroads, offering to public transports new possibilities of connections and services. The strategy consists in proposing a regulation envelope which will define the silhouette of the district and its density. Inside this "virtual" envelope, the buildings are arranged according to the programs as well as the property and economical opportunities. These pieces of city get built "under" this envelope with freedom, fluidity and flexibility. Each architecture has its own architect, its own design, its own client, but all of these architectures show gradually the specific outline of this territory. The movements of this silhouette are interralated with the urban and geophysical environment, scoring with high points the gates of the district, or accompanying with low points the surrounding streets. This park has to become the great public space, the spine of the district. It is this silhouette that shall be controlled by the public power, the private power being in charge of the building varied and mixed architectures.