Image The frenzy of La Tomatina in 2016. Credit... Biel Alino/Agence France-Presse — Getty Images

According to local lore, it started at the end of World War II, when a street brawl broke out near a vegetable store. So much fun was had that it became an annual event. It was banned for a time in the 1950s, under the Franco dictatorship, but it was eventually declared an official festival after residents protested by holding a “tomato funeral.”

The one-hour food fight won’t start until a competitor climbs a greased pole to retrieve a ham, as the crowd hoots and cheers. Trucks bring in low-quality tomatoes from the province of Extremadura, and water cannons are fired to start the battle. (Participants are encouraged to squish the tomatoes to lessen their impact.)

Afterward, the cobble streets are hosed down, and the acidity of the tomatoes is said to leave them shining.

Karen Zraick contributed reporting.

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