The Astronomical Clock Tower, situated in Prague’s Old Town Square, just celebrated its 600th anniversary. And to help mark the occasion, artists projected visuals mappings onto the facade – ones that illuminated the history and symbolic significance of the tower for the crowd. These light shows are getting a little en vogue. Cambridge University recently punctuated its 800th anniversary celebration by turning its buildings into a canvas. And Ukraine marked its independence this year with a light show of its own.