A runaway truck ramp, runaway truck lane, escape lane, safety ramp, emergency escape ramp, or truck arrester bed is a traffic device that enables vehicles which are having braking problems to stop safely. It is typically a long, sand- or gravel-filled lane connected to a steep downhill grade section of a main road, and is designed to accommodate large trucks or buses. It allows a moving vehicle's kinetic energy to be dissipated gradually in a controlled and relatively harmless way, helping the operator stop it safely.