regulations only permit one section of them on the course. Tree logs of maximum diameter 40 cm are sometimes used as barriers in North America. Since outside assistance is allowed, pits are included to provide a consistent area for this to occur. A pit to the right of the course is normal since most riders dismount to their left. In larger events a separate pit lane is featured so only those wishing a new bike or other assistance need enter the lane (this type was debuted at the Zeddam, Netherlands World Cup of January 1999). In some cases pits are provided in two different parts of the course. Long-format races, in which riders compete cross country also exist. Examples include the Three Peaks Cyclo-Cross, a 61 km race, Barry-Roubaix, and the American UltraCX Championship Series which consists of seven stages ranging from 80 to 115 km. Technique Although cyclo-cross courses are less technical than those of mountain biking, each particular obstacle requires specific technical abilities of competitors. For example, dirt single-track and streams (like in mountain biking) are also sometimes integrated into the course, depending on the location, both of which require rider experience and technique. Some course sections are extremely muddy, wet or even snowy in the winter, and others are dusty and sandy. Most of these conditions are usually considered too extreme to be ridden with the standard 32c tire, and so much of the challenge of cyclo-cross lies in maintaining traction through loose or slippery terrain at speed. The power of the rider is generally higher over the whole duration of a cross race to overcome greater amounts of rolling resistance from loose dirt or grass. Also common are steps, barriers, ditches, stairs, steep slopes and very deep mud or sand which all require running while carrying the bicycle. As a result, cyclocross is also known as the "steeplechase of cycling." This approach was invented by Octave Lapize and proven by Eugène Christophe who in 1913 had to carry his broken bike down the Tourmalet during the Tour de France. Although getting off and on a bike sounds simple, doing so in the middle of a quick-paced race is difficult. Being able to fluidly dismount at speed, pick up and carry the bike, then put it back down and remount smoothly without losing momentum requires practice and skill, as the competitor may do this dozens of times