Tower of Pisa

This guide to the Tower of Pisa follows the story behind Galileo Galilei's falling-bodies experiment, said to have toppled two thousand years of Aristotelian physics from these very steps. It traces the tale to Vincenzo Viviani, the only source who wrote it down decades after Galileo died, and asks whether the drop ever happened or was only reasoned out in his head. You'll also hear how the tower began leaning while builders were still three stories up, and how later masons bent the structure rather than straighten it. Look for that curve in the stonework as you circle the base.