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.

Revelers douse themselves in grape juice and wine Image: Eduardo Sanz/Europa Press/ABACA/picture alliance

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 red scraves symbolize unity with Pamplona's patron saint Image: Ruben Albarran/Anadolu Agency/IMAGO

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