The Campanile (belltower) by Giotto, stylish and soaring, is 82 meters high and integrates armonically with the surrounding environment dominated by the Brunelleschi's dome. Giotto made the project in 1334 but directed the works only for 3 years, up to his death on 1337, when it was built only the first series. The construction was completed at the end of XIV century, strictly following Giotto's project. The sculptures of the first series, nowadays exposed inside the Museum of Opera del Duomo and replaced by copies, had been done by Andrea Pisano and Luca delle Robbia.

In front of the cathedral we find the Battistero (baptistry), a circular building where took place the cerimonies of baptism, in Romanic style and covered with white and green marbles. The most important elements of Battistero are the bronze doors by Lorenzo Ghiberti and Andrea Pisano. The northern door, divided into small panels with canvas, is the one Ghiberti made after he had won the contest featuring also Brunelleschi, Donatello and Jacopo della Quercia.

The door in front of the Duomo, the eastern one, is the renowned "Porta del Paradiso" (Heaven's Door, so defined by Michelangelo) where Ghiberti represents in large golden panels some scenes from the Bible (Old Testament). The interior is richly decorated by polychrome marbles with oriental motifs and wonderful mosaics covering the dome, performed by the major mosaicists of the time, who were called to work here.

In the piazza we find also the Museum of the Opera del Duomo (Works of the Catherdal), where are collected some precious elements and fragments from the Cathedral, the Campanile and the Battistero, replaced on original locations by copies. Among them the renowned "Cantorie" by Donatello and Luca della Robbia, which originally covered the chorus loggias inside the Cathedral of Lucca.