Piazza del Duomo

This guide to Piazza del Duomo in Pisa opens with a nineteen-year-old Galileo Galilei, bored during Mass in fifteen eighty-three, timing a swinging lamp against his own pulse. From there it widens to the whole square: the cathedral begun in ten sixty-four with plunder from a naval victory, the Baptistery started in eleven fifty-two and famous for its long echo, and the Camposanto holding soil said to come from the Crusades. Historians have long doubted the lamp story, since the fixture shown to visitors today wasn't hung until after Galileo left Pisa. Clap once inside the Baptistery and count how long the echo lasts.