Facing the Duomo, the octagonal, green and white Baptistry is most famous for the gilded bronze bas-reliefs adorning its eastern doors, designed by Lorenzo Ghiberti in 1401 and completed 20 years later. The panels on the Baptistry are duplicates. The original panels are now housed safely in the Museo dell’Opera del Duomo. The moniker “Porta del Paradiso” (Gate of Paradise) was coined by Michelangelo when he first set eyes on the panels.
The south side doors, depicting the life of Saint John the Baptist, were designed by Andrea Pisano (1336) and the north side doors, illustrating the New Testament and the four Evangelists and four fathers of the church, were done again by Lorenzo Ghiberti (1403-24). The interior contains several mosaics from the 13th-century and the tomb of Baldassare Cossa (aka the antipope John XXIII, 1370-1419), sculpted by Donatello.