Battistero di San Giovanni - Baptistery of St. John

The Florence Baptistery or Battistero di San Giovanni is a religious building in Florence (Tuscany), Italy, which has the status of a minor basilica.
The octagonal Baptistery stands in both the Piazza del Duomo and the Piazza di San Giovanni, across from the Duomo cathedral and the Giotto bell tower. It is one of the oldest buildings in the city, built between 1059 and 1128. The architecture is in Florentine Romanesque style.
The Baptistery is renowned for its three sets of artistically important bronze doors with relief sculptures. The south doors were done by Andrea Pisano and the north and east doors by Lorenzo Ghiberti. The east pair of doors was dubbed by Michelangelo "the Gates of Paradise".
The Italian poet Dante Alighieri and many other notable Renaissance figures, including members of the Medici family, were baptized in this baptistery. In fact, until the end of the nineteenth century, all Catholic Florentines were baptized here.
The Baptistery has eight equal sides with a rectangular addition on the west side.
The sides, originally in sandstone, are clad in geometrically patterned colored marble, white Carrara marble with green Prato marble inlay, reworked in Romanesque style between 1059 and 1128. The pilasters on each corner, originally in grey stone, were decorated with white and dark green marble in a zebra-like pattern by Arnolfo di Cambio in 1293.
The style of this church would serve as prototype, influencing many architects, such as Leone Battista Alberti, in their design of Romanesque churches in Tuscany.
The exterior is also ornamented with a number of artistically significant statues by Andrea Sansovino (above the Gates of Paradise), Giovan Francesco Rustici, Vincenzo Danti (above the south doors) and others.
The design work on the sides is arranged in groupings of three, starting with three distinct horizontal sections. The middle section features three blind arches on each side, each arch containing a window. These have alternate pointed and semicircular tympani. Below each window is a stylized arch design. In the upper fascia, there are also three small windows, each one in the center block of a three-panel design.
The apse was originally semicircular, but was it was made rectangular in 1202.
The vast interior of the Baptistery recalls the interior of the Pantheon in Rome. The interior is rather dark, light entering through small windows in the ambulatory and through the lantern. The interior is divided in a lower part with columns and pilasters and an upper part with an ambulatory. The Florentines didn't spare any trouble or expense to decorate the baptistery. The interior walls are clad in dark green and white marble with inlaid geometrical patterns. The niches are separated by monolithic columns of Sardinian granite. The marble revetment of the interior was begun in the second half of the eleventh century.
The rectangular apse was faced with mosaics in 1225.