Road running is the sport of running on a measured course over an established road. This differs from track and field on a regular track and cross country running over natural terrain.
These events are usually classified as long-distance according to athletics terminology, with races typically ranging from 5 kilometers to 42.2 kilometers in the marathon. They may involve large numbers of runners or wheelchair entrants. Since the late 2010, some road running events also offer Nordic Walking as a separate competition along the same route. The four most common World Athletics recognized distances for road running events are 5K runs, 10K runs, half marathons and marathons.