The risk caused by transportation of hazardous materials can be reduced by routing, that is by the choice of alternative less risky paths than those usually preferred by truck drivers. In order to solve the routing problem a new model named OPTIPATH has been developed, offering a wide set of different optimisation strategies, optionally including compliance with risk acceptability criteria. The OPTIPATH methodology has been integrated in the TRAT4-GIS software for transportation risk analysis. In this paper the application of OPTIPATH to a complex Italian real-life scenario is outlined. The main aim of the work is to show the capability of the methodology in highlighting the trade-offs among strategies for the selection of the preferred solution and the importance of TRAT4-GIS in offering help to administrators involved in the decision-making process which characterises land-use and transportation planning activities. (C) 2008 Published by Elsevier Ltd.