Additional renewable generation, particularly photovoltaic, will be localized primarily at the distribution level. The same can also be expected for electrical loads, which will increase due to the more widespread use of electric vehicles and electric heat pumps. Distribution system operators have several options for dealing with these transformations. Possible solutions range from classic network reinforcements to the adoption of advanced control solutions. In order to determine the best approach from an economic, regulatory and technical perspective, we need to perform extensive simulations on a large number of real distribution networks. However, network data of real distribution networks is generally not public. This paper shows how a method for generating synthetic networks can be integrated with available public data in order to obtain realistic distribution network models for a specific area. The approach is used to reproduce the distribution networks of the Italian electricity system, modeling its electrical structure, loads and connected generators. These networks can be used to study scenarios of future development of distribution networks.