More than 12,000 people gathered in the center of Pamplona in northern Spain on Monday to celebrate the start of the Festival of San Fermin, known for the running of the bulls.

The festival kicked off with the traditional "Chupinazo," a small rocket fired from the town hall balcony over a jam-packed plaza.

The revelers celebrated by pouring wine and grape juice over each other, while  holding up red scarves, singing and dancing,  and shouting "San Fermin, San Fermin, San Fermin."

The first running of the bulls will start on Tuesday morning, and take place every day until July 14.

At 8:00 a.m. several 600-kilogram fighting bulls will be unleashed through the narrow streets of the Old Quarter along an 848-meter course towards a bullring with hundreds of people in front of them.

Dozens of people are injured every year, and there have been 16 fatalities since 1924.

In the evening, some the same bulls that run through the streets are killed in a bullfight. Other festival events include concerts and parades.

As in previous years, animal rights activists protested against the running of the bulls, with dozens seen wearing bull horns and covered in red paint

Pamplona and the running of the bulls provided the backdrop for US author Ernest Hemingway's first major novel, "The Sun Also Rises," which turns 100 years old this year. Hemingway's novel helped make the running of the bulls famous around the world.

Every year, the festival draws visitors from Europe, Australia, Asia and the United States. The festival dates back to the late 16th century and honors Pamplona's patron saint, San Fermin.

Edited by: Zac Crellin

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