The distance of a Thoroughbred horse race varies from track to track
In the US, the Belmont dirt track is the longeset at 1 1/2 miles.
walking around a standard track is 1/4 miles
There are approximately 233,000 miles of railroad track in the United States and back in 1840 there were 21,000 miles of railroad track
It depends on the horse.
The ancient Olympics race track was 500 miles long.
Around 12000 miles