Michigan Stadium
"This is one of the first incidents that involved a sports venue," Michigan athletic director Dave Brandon told the news. "All of us who host sporting events at large venues — if you don't pause for a moment and think about that, I think there's something wrong with you."
The News reports that the two large athletic departments are in constant contact with Homeland Security and that the 2010 renovation of Michigan Stadium made it easier to empty in case of an emergency.