35-Yellowstone Natl Park, WY, Places we Visit-Year 1 Back at Yellowstone today where we got stuck in a traffic “jam”…bison stampeding along the road! June 18, 2013 paula In Yellowstone today we were stopped in a traffic “jam” for over 20 minutes as a bison herd moved along the road. They were on both sides of our car and at one point they started running right past my window! Click on the picture to see the video: