Abstract: The installation comprises a roadway having at least some segments provided with longitudinal reference marking (10) for a nominal path, and vehicles (18) each carrying an assembly providing guidance by controlling a steering axle, having a module for forming an image of the road ahead of the vehicle (18) and for processing the image of the marking, and an optical guidance module calculating the orientation to be given to the wheels of the steering axle to follow the nominal path, and a steering servo-motor controlled by the guidance module. At at least certain segments of the road carry lateral guides (14, 16) and the vehicles, whose front axles at least are steering axles, are provided on each axle with vertical-axis guide wheels (24) designed to press against the guides (14, 16) in the event of the vehicle departing excessively from a nominal path on the road.