Endurance riding is defined by the American Endurance Ride Conference (AERC) as "An athletic event with the same horse and rider covering a measured course within a specified maximum time."

Endurance rides are races which vary in distance between 50 and 100 miles and are covered in a single day. The horse with the fastest time is the winner providing the horse meets the 'fit to continue' criteria as determined by a veterinary staff. The horses are monitored by veterinarians throughout the ride at predetermined check points and will be withdrawn from the ride if they are judged to be unsound or metabolically unfit. Each ride has mandatory rests or 'holds' for the horses throughout the ride.

Some rides are longer than 100 miles but are completed over a period of several days with the horses typically covering 50 miles per day.

Most endurance rides also have a shorter novice ride of about 25 miles. These rides are not considered endurance rides by AERC but are referred to as Limited Distance rides.

Although endurance rides are technically 'races' many (if not most) riders participate for completion rather than placing. To these riders the satisfaction of completing 50 or 100 miles on a sound horse is the prize.