* Breed: Thoroughbreds and Quarter Horses are known for their speed.
* Training: A trained racehorse will run much faster than an untrained horse.
* Distance: Horses can sustain high speeds for shorter distances, but their speed will decrease over longer distances.
* Individual horse: Just like humans, each horse has its own unique capabilities.
Generally speaking:
* A trained racehorse can reach speeds up to 70 kilometers per hour (43 miles per hour) over short distances.
* Average horses can maintain a speed of around 40 kilometers per hour (25 miles per hour) for a sustained period.
It's important to note that these are just estimates. The actual speed a horse can run will vary based on the factors mentioned above.