In this paper we study the problem of finding Origin–Destination (O–D shortest paths in urban multimodal transportation networks, aiming at minimizing the overall cost, time and users' discommodity associated with the required paths. We present an approach based on the classical shortest path problem on a network representing the urban multimodal transportation system, i.e. the private, the public and the pedestrian modalities. Our idea is to make use of an ad hoc utility function for weighing the arcs both with their cost and time and considering at the same time the preference of the users related to all the possible transportation modalities. In particular, a utility measure is presented taking into a proper account the different users' propensities. The proposed approach has been developed for analysing the urban transportation network of an Italian city; the first experimental results are given in the paper.