Florence Baptistery, Baptistery in Piazza San Giovanni, Florence, Italy

The Florence Baptistery is an octagonal building of white stone clad in alternating dark and light horizontal bands, standing between the cathedral of Santa Maria del Fiore and the Archbishop's Palace. Its lower façade has three large arched openings divided by dark columns, with smaller arched windows and rectangular panels above; a shallow eight-sided pyramidal roof rises to a lantern topped by a golden sphere and cross. Inside, two levels of dark green and white stone form geometric patterns of squares, circles and crosses, with arched windows and small mosaic panels above.

No documents on its construction survive; masonry analysis links the lower sandstone levels to Santi Apostoli and later parts of San Pier Scheraggio, pointing to the 1060s or 1070s. A 2024 hypothesis credits Beatrice of Lorraine, Matilda of Tuscany and Pope Gregory VII, with Bishop Ranieri supervising. The south bronze doors were made under Andrea Pisano, the north and east doors under Lorenzo Ghiberti.

The octagonal plan of the building follows ancient models and symbolizes the eighth day, when Christ rose from the dead. Inside, a gold-shimmering mosaic covers the entire dome and shows scenes from the life of John the Baptist alongside the Last Judgment.

The baptistery stands in Piazza San Giovanni, between the cathedral and the Archbishop's Palace, and is entered from that square. The interior floor is plain and light-toned, with low barriers set in front of the wall panels, so visitors walk around the perimeter rather than through the centre. The building holds the dignity of a minor basilica and still serves as a place of prayer.

The south doors were made by Andrea Pisano's workshop in the 14th century, while Lorenzo Ghiberti led the teams that cast the north and east doors in the 15th. Donatello and Michelozzo created the first Renaissance funerary monument inside, that of Baldassare Cossa.