This happened to my husband and me at the Old Faithful site.
No one did anything to provoke the stampede. The herd simply charged through the crowd. Thankfully, no one was injured but it was very scary. People were jumping away in every direction.
Later in the evening at a “Meet the Ranger” event, the ranger asked,” What is the safe distance a visitor should make from the wildlife?” I replied, As far away as possible!”
Oh!...I **love** trolls! They are easily enraged and quickly melt into blubbering puddles of personal insult. ( Sooooo.!..Much!.. Fun! ..To! ... Watch!.). :)