This is undoubtedly one of England's strangest things to do in May, but its tradition dates back to the 17th-century.
The aim – for those bonkers enough to compete – is to run up a ridiculously steep hill as fast as you can, while carrying a sackful of wool on your back.
Once competitors reach the bottom, they hand the sack to a team-mate who has to leg it back up the hill. If you're feeling tired just thinking about it, the good news is you don't have to join in; teams spend months training for the event so most people who come here are happy to just watch.
Tetbury was once an important town for Cotswold wool traders, and the races are thought to have originated with young drovers who wanted to show off in front of the local ladies. Around this, the town celebrates with a street fair, local stalls and amusement rides.
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