There are a lot of reasons to go for a run. Exercise. Marathon training. Meeting hot singles in your area, per TikTok's latest dating "hack." But one reason to slip on those sneakers appears to eclipse the rest — running for your life from a pack of angry bulls. Dating back to roughly the 14th century, the running of the bulls has spanned generations, not only serving as a cornerstone of Spanish culture but also generating some striking images. 

From a near-gore experience to an appearance from literary icon, Ernest Hemingway here are 20 black-and-white photos from Pamplona's iconic running of the bulls.