This paper addresses the problem of supporting public decision makers in the data analysis of the territory they are responsible for. Most of the Italian territory consists of the so-called inner areas, which are primarily rural areas usually far from main centers that provide education, health and mobility services. A project that analyzes inner areas is reported; it has two main objectives. A first one is to identify proper clusters of such areas so that smaller areas can be grouped together in order to share important services in the best and more economic way; different algorithms are used to identify relevant parameters and to cluster inner areas. The second objective is to create proper visualizations of data of such inner areas, in order to better support decision makers in understanding the data and taking more informed decisions. It is remarked that using visualization techniques without adequate knowledge of their possibilities greatly limits the support that analysts may get from them.