Thousands of daredevil tourists have descended on Pamplona, Spain, for the annual running of the bulls that began today. Four were injured on the first day, including one American, though nobody was gored. As Time reports, sprinting ahead of six half-ton angry bulls is pretty dangerous, but many injuries result from slipping on cobblestones or knocking into other runners.
Bulls have been run from corral to bullfighting ring in Pamplona since 1592, though people didn’t join in until the 19th century. Ernest Hemingway immortalized the tradition in The Sun Also Rises, in which he mentions the secret of many runners’ bravery: copious wine and sangria. There hasn’t been a death since 1995, when an American was gored after he broke Pamplona’s cardinal rule: If you get knocked down, don’t try to get up.