Baptistery of San Giovanni

The octagonal baptistery opposite the cathedral, one of the oldest buildings in the city. Its bronze doors are the reason most people stop: the east doors, Ghiberti's 'Gates of Paradise', are copies on the building, with the originals in the Museo dell'Opera del Duomo. Check whether the mosaic ceiling is under restoration before you pay to go in.

Opening times and prices change. Check the official site before you go.