Curb

A curb (also spelled "kerb") is a raised or painted edge that runs along the sides of a racing track, marking where the official track surface ends and helping drivers see the boundaries of the course.

You'll find curbs on almost every racing circuit in the world, positioned along the inside and outside edges of corners and sometimes on straight sections too. They're usually painted in bright, alternating colors—most commonly red and white stripes—so drivers can easily spot them while traveling at high speeds. Think of them like the lane markers on a highway, except they're three-dimensional and serve multiple important purposes.

The main job of a curb is to show drivers exactly where the track limits are. Without these markers, it would be difficult to tell where the legal racing surface ends, especially when you're moving at 200 miles per hour. They also prevent drivers from taking shortcuts by cutting across the inside of corners, which would give them an unfair advantage over competitors who stay on the proper racing line.

Experienced drivers often use curbs strategically in a technique called "kerb-riding." By carefully driving over the inside curb during a corner, a skilled racer can straighten their path slightly, which allows them to carry more speed through the turn. However, this requires precision—hitting a curb too hard or at the wrong angle can unsettle the car, slow it down, or even cause damage to the suspension and underside of the vehicle.

Not all curbs are created equal. Standard curbs are slightly raised and have a serrated or rippled surface that vibrates the car when you drive over them. Sausage curbs are much taller and more aggressive, designed specifically to punish drivers who try to cut corners—these can actually launch a car into the air if hit at speed. Some tracks use painted curbs that are simply lines on the pavement, while others have "rumble strips" that make a loud rattling noise to alert the driver they've gone off the ideal path.

From a safety perspective, curbs help slow down cars that run wide or lose control, potentially preventing them from hitting barriers at full speed. They also protect the track surface itself from breaking apart under the extreme forces generated by racing tires pushing hard through corners.

The design and placement of curbs are carefully planned by track engineers to balance safety with competitive racing. Some curbs are meant to be used aggressively, while others serve as a clear warning that drivers have gone too far. Learning which curbs can be attacked and which should be avoided is an essential skill that separates good drivers from great ones.