Cyclo-cross is a type of bike racing that takes place on mixed terrain, including grass, mud, sand, and pavement, with riders often carrying their bikes over obstacles. The races are held on short, looping courses with sharp turns, steep slopes, and barriers that require quick dismounts and remounts. Cyclo-cross bikes resemble road bikes but have wider, textured tires for better grip. Riders need speed, endurance, and bike-handling skills to navigate the constantly changing conditions, making it a physically demanding and technically challenging cycling discipline.