A covering device to be fastened opposite an opening of a motor vehicle and comprises at least one element which is fastened on the circumference of the opening, wherein a covering unit is displaced in an expansion direction between a storage position, in which the covering unit is released from the opening, and a covering position, in which the covering unit is extended opposite the opening, wherein the covering unit comprises a network of optical fibers having lateral light scattering. The network of optical fibers is supplied with light by at least one light source which is fastened on the element and, in order to supply the network of optical fibers with light, can illuminate ends of the optical fibers of the network in at least one illuminating position of the covering unit.