This paper describes the extensive test that has been performed to validate the vision-based automatic vehicle guidance system developed within the ARGO project at the University of Parma. After a brief introduction dealing with the main characteristics of the system installed onto the ARGO vehicle, the paper describes the 'MilleMiglia in Automatico' tour, its schedule and features. Finally the paper discusses the results collected during the tour and analyzes possible solutions that may be implemented in the future to make the system more robust with respect to the problems encountered during the test.