CNN Senior National Correspondent David Culver reports a nail-biting account of the world-renowned and controversial running of the bulls from the streets of Pamplona, Spain.Culver follows a group of runners in the weeks and days leading up to the annual running of the bulls at the San Fermín Festival in Pamplona, a tradition held since 1591. Since record-keeping began in 1910, 16 people have died participating in Pamplona, and the most recent bull run fatality occurred just last week in Valencia, Spain. Culver embeds with the group as they prepare for the perilous event, guided by experienced runners who have entered hundreds of bull runs and even been gored. As the day of the run approaches, Culver decides to suit up in the traditional white garb and red scarf and try it out himself – well aware of the dangers but hoping to understand the thrill some find."I was well aware of the dangers – and what some might consider to be the insanity – of running with the bulls," said Culver. "But having met folks so deeply passionate about and protective of this controversial tradition, I wanted to join for one of the eight bull runs, if only to try to better understand the thrill they speak of." Culver added, "Turns out, one run was enough for me!"Culver also investigates the highly divisive activity of bullfighting, the ritual killing of the bulls following the morning's run. Bullfighting is condemned by animal rights groups and banned in many countries. Still, the tradition persists throughout Spain, with many there considering it an integral part of their heritage and culture.