Economic development and environmental challenges require to identify alternative urban forms and original way to build cities. Inventing new ways of living and of being mobile, stopping the urban sprawl, increasing the density of the existing city, giving new sense and value to escheated property in shrinking cities, conceiving the development of territories by connecting the local and the global : all of these requirements contribute to create another urban reality, subsumed into the general term of “sustainable city”, in absence of a more accurate content.

In actuality, the sustainable city is an accumulation of urban experiences, all of which are uncertain experiments of a project whose aim is to establish, in an everyday rhythm and in close proximity, a change whose understanding requires a long-term, global-scale perspective. This project of development creates its own content by being implemented, unlike utopias of modernity which provide the framework before defining urban use.

The utopia of a sustainable city is not a counter model nor an ideal city : it stands as the transcending of an exhausted urban reality. It is an utopia of everyday life, built in the context of the necessary adaptation to a change that is already underway but not perceived. To apprehend the content and forms of the process in order to understand its principles and possibilities and to eventually influence them, is an issue that is both scientific and practical.

Thus, understanding the incremental nature of change is the topic around which the research must be organized. We hypothesize that a restrospective review of the changeover to a technical society during the 19th century has an heuristic value. If the confrontation to innovation was sometimes sudden, this changeover was more akin a gradual shift towards modernity than a break. The current change is another way of illustrating what is less like a fundamental reversal than a dialectical continuity of a process.

Space, defined as a historically situated social production, is the material of reference of the approach proposed in the following project. The social production will be investigated by intertwining its material dimension (layout of the spaces and places) and its intellectual one (imaginations and representations). The temporal dimension will be investigated through the identification of its main historical moments as a perspective of comprehension, but also through the analysis of urban continuity. In such a perspective, the approach is based on the confrontation of points of view that pertain to different disciplines (those of geographers, historians, researchers in aesthetics, computer scientists). The metropolitan area of Lyon and Saint-Etienne is the field selected for this research, which focuses on “experimental spaces” whose marginal position enhances the visibility of change: Vaise and the “chemical valley” to the North and the South of Lyon, Givors and the valleys of Gier and Ondaine, to the East and West of Saint-Etienne. Archival materials, public and private documents (surveys, statistical data, local regulations, images, maps, museum collections), usual human sciences material (surveys and interviews) will be used.