How far can a horse run at full speed before he gets tired?

A horse can maintain a full-speed gallop for a few miles. Two to 3 miles is about the maximum distance for which even a well-conditioned horse can maintain a top speed. Horses can, however, cover very long distances at slower speeds.

The Pony Express averaged 9 to 10 miles per hour over 15- to 25-mile stages, changing horses between stages. Many very long-distance rides, called endurance rides, have been completed on horses, in which the horse has to cover 100 miles in less than 24 hours. In the Middle East, as of 2014, 26-mile races on horseback can be completed in around an hour.