Austin Bridge Troll

Latest from #UT PD: After arrest of man exhibiting "troll-like behavior...students could once again cross the bridge w/o answering riddles" pic.twitter.com/AM9dZLI1GG

— Lauren McGaughy (@lmcgaughy) November 1, 2016

And for the life of me I can't remember the story of a bridge troll and riddles. Wasn't there some fable we were told as kids?  Even the Google has failed me. (Although I accidentally stumbled upon Three Billy Goats Gruff which I haven't thought of in decades.)