See the 2013 dyeing of the Chicago River -- not to mention a flying leprechaun! The river is dyed emerald green every year for St. Patrick's Day.
CHICAGO, IL - MARCH 16: Workers begin dying the Chicago River green to kick off the city's St. Patrick's day celebration on March 16, 2013 in Chicago, Illinois. (Photo by Scott Olson/Getty Images)
CHICAGO, IL - MARCH 16: A man dressed as a leprechaun entertains the crowd on a water propelled Flyboard while workers dye the Chicago River green (Photo by Scott Olson/Getty Images).