Nearly every I-70 traveler has likely noticed the ‘runaway truck’ ramps on the side of the route and many have likely wondered what it’s like to see them in use.

A video recently posted to Reddit has drawn attention to runaway truck ramps, showing a truck speeding up a runaway truck ramp, then sliding back down a bit, kicking up dirt.

According to the Colorado Department of Transportation (CDOT), if a driver needs to use a runaway truck ramp they should maneuver the truck into the far right lane before approaching the ramp, then steer straight while trying to keep the wheels aligned as the truck approaches the runaway ramp. At that point, a driver should stay in the center to avoid rolling over. Once the truck is stopped, the driver should call 911 to report the incident.

CDOT also states that there is no fee, penalty, or fine for using runaway truck ramps. However, drivers will have to pay the towing expenses. According to the Colorado Sun, an easy removal can cost around $1,500, though that can quickly climb.

According to CDOT, runaway truck ramps provide refuge when a truck loses its brakes while traveling at high speeds on steep downgrades. The ramps are usually located on steep sustained grades in mountainous areas. Colorado has five along the I-70 mountain corridor.

CDOT also provides this map of the locations of Colorado’s runaway truck ramps. The map also brake cooling and chain station locations.