Alvaro Barrientos, Associated Press
Revelers hold up traditional red neckties during the "Chupinazo," the official opening of the 2008 San Fermin fiestas in Pamplona, Spain, Sunday. The fiestas, held since 1591, are most famous for the running of the bulls through the town's streets.

PAMPLONA, Spain — Tens of thousands of people crowded into Pamplona's main square Sunday to celebrate the launching of a rocket that each year marks the beginning of Spain's most famous bull-running festival.

"Men and women of Pamplona, all hail to San Fermin," town councilor Uxe Barkos said from a balcony overlooking the crowd before lighting the fuse, signaling the beginning of nine days of uninterrupted festivities in the town.

The San Fermin festival is known around the world for its running of the bulls. The mood and tradition was made famous in 1926 by Ernest Hemingway in his novel "The Sun Also Rises."

Most revelers sported traditional white trousers and shirts with a red neckerchief tied at the front. After a night of drinking, all were covered in copious amounts of wine, sangria, sparkling wine and other drinks.

Residents poured buckets of water over the crowd from their balconies to help cool down the revelers.

During the celebrations, police found the body of a young man who apparently died early Sunday by falling 33 yards (30 meters) from an ancient wall that circles the old quarter of Pamplona. Police were trying to determine if he was one of the many foreigners attending the festival, a city spokesman said on condition of anonymity in keeping with government rules.

At last year's festival, an American man and his Spanish girlfriend died at the same spot when they accidentally fell from the top of the wall.

But Sunday's tragedy had no effect on the fanfare.

Stephanie Degonda, 21, of Minnesota, said she had come to the festival for the first time. "It's incredible. I've never seen anything like it in my life," she said.

Anna Stampy, 22, had traveled halfway around the world from Brisbane, Australia, to also see the festivities for the first time.

"I love it. I'd heard a lot about it, but seeing it in person is truly moving," Stampy said, swigging a bottle of beer.

Marcelo Ledesma, 28, from Asuncion, Paraguay, also was taken aback. "Everyone is drunk; it's impressive," he said.

The first bull run is due to take place today, an event repeated daily until July 14, and all are broadcast nationwide on state television.

Each run takes place at 8 a.m., testing the skills and courage of the participants, who must race alongside six fearsome fighting bulls along 875 yards (800 meters) of narrow, cobblestone streets linking the city's stables to the bullring.

On the afternoon of each day, the bulls must face matadors in the ring.

Since record keeping began in 1924, 13 people have been killed in the event. The last victim was a 22-year-old American gored to death in 1995.

It is customary for several hundred animal rights activists to protest against the cruelty they say takes place during the festivities.

Half naked, they traditionally lie down along the route of the bull run the Saturday before the fiesta, covered in fake blood and bearing placards in different languages asking for the "Abolition of bullfighting," or saying "Bulls have a bloody death in Pamplona."

This year the activists wore on their backs imitation banderillas, the long barbed darts that are stabbed into the bull's neck as part of the bullfighting ceremony.