Horse racing
Endurance racing

The length of an endurance race varies greatly. Some are very short, only ten miles, while other races can be up to one hundred miles. There are a few races that are even longer than one hundred miles and last multiple days. These different lengths of races are divided into five categories: pleasure rides (10–20 miles), non-competitive trail rides (21–27 miles), competitive trail rides (20–45 miles), progressive trail rides (25–60 miles), and endurance rides (40–100 miles in one day, up to 250 miles (400 km) in multiple days). Because each race is very long, trails of natural terrain are generally used.

Contemporary organized endurance racing began in California around 1955, and the first race marked the beginning of the Tevis Cup This race was a one-hundred-mile, one-day-long ride starting in Squaw Valley, Placer County, and ending in Auburn. Founded in 1972, the American Endurance Ride Conference was the United States' first national endurance riding association. The longest endurance race in the world is the Mongol Derby, which is 1,000 km (620 mi) long.
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