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The running of the bulls is an event which captures attention every year, as images of daredevils outrunning charging bulls in the Spanish streets of Saint Fermin are beamed around the world.
Today - as the bulls are released for their brief run down the streets - will be no exception.
The tradition is said to be centuries-old, dating back to when farmers would corral the bulls to the market and young men would attempt to outrun them. It’s since become a popular tradition, and tourist attraction.
But there’s a darker side - the bulls are now run through the streets to make their way to a bullfight, where they will be slowly killed for sport.
Animal rights groups and veterinarians have long condemned the event, arguing it causes severe pain and stress to the animals, and has been banned in several regions, such as Catalonia (which includes Barcelona).
But the town of Mataelpino has found a happier alternative.

A matador prepares to deal the final blow to a bull during a bullfight. Source: www.traslosmuros.com

A matador prepares to deal the final blow to a bull during a bullfight. Source: www.traslosmuros.com
They ended the practice in their streets, and simply by swapping the "u" for an "a", gave the world The Running Of The Balls.
Now residents and tourists attempt to outrun a giant, 100 kg styrofoam ball.