A car travels along a sheathed cable, especially a suspension cable of a bridge, with the cable sheathing being of sheet metal and forming a rabbet projecting radially outwardly and following a helical course in the lengthwise cable direction. The car has at least one drive member engaged in the rabbet grovoe limited on the side by the rabbet. The drive member can be moved by a drive device immovable relative to the car along the lengthwise axis of the cable, but movable on a track concentric with the lengthwise axis of the cable.