Cyclo-cross, which can also be called CX, CCX, cyclo-X or ’cross is a type of bicycle racing. The sport originated as a sport for road racers to keep fit during the cold off season. Races typically consist of many laps of a 2–3 km or 1–2 mile course over various terrain ranging from roads to paths with short steep climbs, off camber sections, and corners. Some undertire conditions involve asphalt, dirt, grass, mud, and sand. The courses are around 90% rideable, as there can also be obstacles requiring the rider to dismount and carry the bike through that section. Most of the races consist of many laps over a short course. This ends when a time limit is reached. The length for senior races is one hour, for lower categories, it’s around 30 or 45 minutes. Most cyclo-cross races are organized in the autumn or winter. The World Championships for cyclo-racing usually takes place around the end of January. The Championships in Canada and the United States are done in November and December. Cyclo-cross bicycles are similar to road racing bicycles. They only differ with their wider tire clearances, knobby tires, cantilever or disc brakes, and lower gearing. Just like other bicycle races, cyclo-cross races involves courses.