Three Master degrees were completed in 2012 at the University of Paris 1; their subjects were the archaeological urban sites of Chartres, Noyon and Le Mans. These studies used a common method, with free GIS tools and relational databases. The aim was to update the documents for evaluating the archaeological heritage of French towns, which are based on principles first drawn up in The Future of London’s Past in 1973, and used in France for 25 years by the National Centre of urban archaeology. In particular, the method applies the notion of urban functional entity to analyse the historic urban space. This article presents some methodological aspects and initial results.