Long distance races are 5000 m long. Marathon races are at least 15 km. Men's marathon has a minimum length of 20 km. Women's marathon has a minimum of 15 km. Most major races are 30 km or longer. There is no maximum distance for marathon races. There is a marathon race that is about 1000 km long on in the Yukon. The longer races are usually broken up into several parts and may be raced over several days. In long distance and marathon races, all racers start at the same time. They do not use "intervals" where the racers are started at different times.