The farthest most horses can sustain a gallop is thought to be around 2 miles, but some Arabian horses can gallop for 2.5 miles before fatigue is a factor. The gallop is the fastest method of movement for the horse, averaging approximately 25 to 30 mph.
The American quarter horse is the fastest horse on record, galloping as fast as 55 mph in short bursts. When a horse is galloping, all four legs leave the ground, making the horse airborne for a split second. In racing horses, stride length is a possible measure of a horse's potential competitive success. Famous racehorses such as Secretariat have comparatively longer strides than their peers. Secretariat's stride was almost 25 feet in length.