The Man vs. Horse Marathon is an annual race over 22 miles (35 km), where runners compete against riders on horseback. The race takes place in the Welsh town of Llanwrtyd Wells every June and takes competitors through some of the countryside’s most picturesque scenery via farm tracks, footpaths and open moorland.

The event started in 1980, when local landlord Gordon Green overheard a discussion between two men in his pub. One man suggested that over a significant distance across country, man was equal to any horse. Green decided that the challenge should be tested in full public view, and organized the first event.

Humans have only won the race twice in 30 years, but top runners usually only finish 10 minutes after the animals (around 2:20 hours). What horses gain in oxygen efficiency and muscle mass, humans make up for in temperature regulation. In the beginning of the race the horses tend to have a 30 minute lead, but toward the end, that advantaged is cut to a couple of minutes. Over the course of the race, humans are more efficient at expelling heat—not to mention they aren’t running with a rider on their back.