Image by Walter Bibikow Getty Images
Pisa's unusual round baptistery has one dome piled on top of another, each roofed half in lead, half in tiles, and topped by a gilt bronze John the Baptist (1395). Construction began in 1152, but it was remodelled and continued by Nicola and Giovanni Pisano more than a century later and finally completed in the 14th century. Inside, the hexagonal marble pulpit (1260) by Nicola Pisano is the highlight.
The lower level of arcades is Pisan-Romanesque; the pinnacled upper section and dome are Gothic.
Pisan scientist Galileo Galilei (who, so the story goes, came up with the laws of the pendulum by watching a lamp in Pisa's cathedral swing), was baptised in the octagonal font (1246). Don't leave without climbing to the Upper Gallery to listen to the custodian demonstrate the double dome's remarkable acoustics and echo effects, every half-hour on the hour/half-hour.