Morphogenesis of urban peripheries in the 20th century : examples from the French Riviera

Résumé En

In this paper, we present the first urbanization and the subsequent transformations of the urban fabric in peripheral areas around the cities of the French Riviera, with a focus on the 20th century. More specifically, two urban sectors are analyzed in the cities of Nice and Cagnes-sur-Mer. Cadastral maps, aerial images and urban plans over a century and a half constitute the main inputs of the analysis. These coastal cities represent two paradigmatic contexts for the French Riviera. In Nice, the first urbanization was channeled by different plans of the street network, with different spatial logics in the 19th and in the 20th centuries. In Cagnes-sur-Mer, planning interventions were much more fragmented and sometimes completely absent. The second after-war period constitutes a paradigm shift in the urbanization process. A general scheme of the different phases of the morphogenetic process is proposed to summarize our main finding. It shows that the observed urban forms can result from different evolutionary paths. At the same time, strong path-dependencies characterize the sequence of the morphological processes. Compact city forms can be catalyzed by a planned urban grid, but can also evolve more spontaneously. Planned tree-like structures with built-up plots blocking the dead-ends produce less evolutive residential forms. Topographic constraints and urban pressure linked to accessibility patterns in a context of urban growth are also important factors in explaining the observed processes.