Dramatic images from the controversial tradition

Spain kicked off one of its most controversial and adrenaline-fueled traditions on Monday: the Pamplona bull run.

As part of the nine-day San Fermín Festival held every year from July 6 to July 14, the event brings more than a million thrill-seekers and spectators from across the globe to the city of Pamplona to watch hundreds of brave revelers get chased through the streets by six large bulls.

At the stroke of 8 a.m. on July 7 of the festival every year, the bulls are released from their corral and charge through narrow alleys, toward the Plaza de Toros, the city’s bullring, where they will later be killed by matadors during the evening’s bullfights.

The runs last roughly three and a half minutes each day. Participants and spectators dress in white pants and a white shirt, with a red sash tied around the waist and a red handkerchief tied as a scarf around the neck. For the participants themselves, it’s a heart-pumping race against time — and sharp horns.

Made internationally famous in Ernest Hemingway’s 1926 debut novel, The Sun Also Rises, the bull runs are dedicated to the city’s patron saint, San Fermín. The tradition dates back to the 16th century when cattle herders used the bull run route to transport animals from the countryside into the city for bullfights, according to Time magazine.

Still, the excitement doesn’t come without perils.

Dozens of runners are injured every year, with a reported 16 deaths since 1924. On the second day of the bull run this year, a man, identified only as being older than the age of 25, was gored by a bull’s horn under his right armpit, highlighting the event’s inherent risks. Seven others were injured and suffered bruises and contusions to the shoulder or head.

Despite the danger, the event’s allure remains undiminished, drawing participants year after year despite the controversy it stirs among animal rights groups.

Here are some of the tense moments captured on camera during this year’s running of the bulls in Pamplona.

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