Running of the bulls bullring, which acts as a funnel as it is much narrower than the previous street. In such cases injuries come both from asphyxia and contusions to those in the pile and from goring if the bulls crush into the pile. This kind of blocking of the entrance has occurred at least ten times in the history of the run, the last occurring in 2013 and the first dating back to 1878. A runner died of suffocation in one such pile up in 1977. Overall, since record-keeping began in 1910, 15 people have been killed in the bull running of Pamplona,
Running of the bulls wooden fences is erected to direct the bulls along the route and to block off side streets. A double wooden fence is used in those areas where there is enough space, while in other parts the buildings of the street act as barriers. The gaps in the barricades are wide enough for a human to slip through but narrow enough to block a bull. The fence is composed of approximately three thousand separate pieces of wood. Some parts of the fence remain in place for the duration of the fiesta, while others are placed and removed each morning. Spectators can