ABSTRACT
The construction of the cathedral of Firenze was begun in the year 1296, with the works related to the extension of the ancient church of Santa Reparata: it was designed byArnolfo (1240,1302).The design included a great dome, based on an octagonal base, to be erected in the eastern end of the church.The dome is an unusual construction of the Middle Ages, (Wittkower 1962): Arnolfo certainly referred to the nearby octagonal baptistery San Giovanni, so ancient and revered that the Florentines believed it was built by the Romans, as the temple of Ares, hypothesis which was not confirmed by excavations, that set the date of foundation is between the V and IX century (Rocchi 1996).
