The invention relates to a lane guidance system (10) for guiding and stabilising a vehicle axle along a lane, comprising a Watt linkage arrangement for connecting, in relatively movable manner, the vehicle axle to an underside (x) of a chassis, wherein the Watt linkage arrangement has at least two Watt linkages (20) which correspond in their guide direction (F) and are arranged in the transverse direction (Q), wherein the Watt linkage arrangement has a guide element (30) for guiding the vehicle axle along a straight line in the guide direction (F). According to the invention, the Watt linkages (20) are fastened, by means of their longitudinal ends (22, 24), to the guide element (30) and to the chassis, wherein the guided vehicle axle is a trailer axle (A) of a semitrailer.