Every time Robyn Gershon, who is leading a study of the World Trade Center evacuation, checks into a hotel, she takes the stairs down from her room. She knows that most hotel stairs take a confusing path through back rooms and empty onto unexpected streets. (I once did this in a hotel in Manhattan and ended up in the kitchen. A supervisor, assuming I was an employee leaving for a break, asked to search my bag. Apparently not very many guests took the stairs.)
