Funded by the French National Research Agency, the ALPAGE project (ALPAGE is a French acronym for " diachronic analysis of the Paris urban area: a geomatic approach ") aims at producing data and tools to understand the long term relationships between spaces and societies in Paris. The main laboratories or institutions involved in this project are LAMOP (project leader), ArScAn, LIENSs, L3i, COGIT, IRHT, the Parisian topography centre, APUR. The above come together to collaborate on building a Geographic Information System for the Parisian area in the preindustrial period. The creation of such a GIS enables to reconstruct the oldest parcel plan of Paris, the Atlas made by Vasserot between 1810-1836, and to spatialise historical data from the Middle Ages and modern times (walls, aristocratic mansions, sewers, floods, manors, parishes, etc.). When linked with the old urban fabrics, these data show the diachronic structure of the urban morphology. Finally, an interesting development of the project, originally unplanned, has been to provide all this new knowledge to everyone through a digital webmapping platform : http://alpage.tge-adonis.fr/
