The MAPPA - Methodologies Applied to the Predictivity of Archaeological Potential – project (University of Pisa) is a research project aimed at the creation of a replicable predictive model of a map of archaeological potential in an urban area. The starting point has been a well‐organized data archive, so the research group focused on developing a webGIS and the Open Data application. The webGIS (MAPPAgis) offers the archaeological information layer, the building archaeology layers, the historical mapping layer and the geomorphological layer. The optimization of MAPPAgis is intrinsically linked to the MOD (MAPPA Open Data), the first Italian archaeological open data archive, that collects datasets of archaeological raw data and preliminary reports. Through the use of spatial and geostatistical analysis, the cooperation with geologists to analyze the ancient surrounding environment and with mathematicians to elaborate a specific algorithm, we realized a predictive mathematical model. Using the same criteria as those for assigning importance to web pages by search engines, we identified the relations that exist among finds, both in spatial and in functional terms. All these open products have a strong impact on archaeological heritage protection, territorial planning and historical knowledge.