About 4,000 people - dressed in everything from thongs to superhero costumes - dodged 1,000-pound (about 450 kilos) bulls as they sprinted down a quarter-mile (0.4 km) dirt track on Saturday in rural Virginia's version of the running of the bulls in Pamplona, Spain.
It was the first event of what promoters say will be a national, 10-city bull-running tour modelled on the annual Pamplona event.
"I just didn't want to die, to get trampled by bulls and die," said Cat Jones, 22, who works in engineering and travelled from New York City for the run.
"It was a rush ... a shot of adrenalin," she said.
Jones had such a thrill dodging bulls and watching them race by at breakneck speed that she paid USD$30 ($38) to run again in the afternoon.
The first six runs were conducted with about 500 runners each, chased by 12 bulls, and the last run featured 24 bulls chasing about 700 runners.
About 8,000 people came to watch the runs, said Rob Dickens, co-founder and chief operating officer of the Boston-based Great Bull Run. Most of those who signed up were 18 to 40 years old, and about 40 per cent were women.
Two runners were taken to the hospital with concussion-like symptoms, according to Great Bull Run.
One other runner saw a medic after being knocked down and stepped on by other participants.
Every participant in the race had to sign a waiver, absolving the organizers of liability in case of injury.
Dickens said it was "doing something dangerous and living to tell the tale" that draws participants to the event.
"I wanted to test myself," said Laurie Blaha, 27, of Richmond, Virginia.
Blaha said she passed the test, conquering the fear and nervousness she had before the bulls ran onto the track.
"It was exhilarating," Blaha said. "I would definitely do it again."
Dickens said the only major problem came on the first run of the day, when the initial group of six bulls stopped about midway down the dirt course.
They didn't start running again until six additional bulls were let out of the gates.
Dickens said they apparently did not have the confidence to run alone, and needed more company.
After that, he said the staff overseeing the bulls began sending 12 bulls at a time.
In nearly all the runs held during the day, the bulls started slowly and then quickly accelerated to a stampede-like pace.
The Virginia run was set on the grounds of the Virginia Motorsport Park, a drag strip south of Richmond.
Animal rights groups, such as PETA, have protested the Great Bull Run, saying the events puts stress on the animals.
Dickens has said the bulls are not harmed and has invited anyone observing someone abusing the animals to report it.
The next Great Bull Run is scheduled for October 19 in Atlanta.
Other cities on the nationwide tour include Houston, Tampa and Los Angeles.