The Dome of Pisa, founded in 1064 and dedicated to S.Maria Maggiore, is a real architectural masterpiece of the Romanic period. The first project for the building was made by the architect Buscheto, who managed to modify the current stylistic forms through a completely innovative and autonomous language.

According to the tradition, the construction of the Cathedral was financed by the spoils coming from the seizure of some Saracen ships in Palermo's port.
To Buscheto (praised in an epigraph on the facade) we owe the inside division into five naves according to the early Christian model of the great Roman churches, enriched by the use of modern Romanic elements as the women's gallery overlooking the central nave and the roofing with groined vaults of the little naves (the central nave, originally covered by a trussed roof, has now a lacunar dating back to the end of the 16^th century).
For the use of really slender piers with an Islamic flavour in the pointed curve arches that divide the side naves, the inside of the Cathedral is more similar to the shapes of a mosque rather than to those of an early Christian Basilica.
The outside does not show the inside division into five naves: the piers allow the lifting of the mainstay of the groined vaults which are thus all on the same level and closed outside by a common slant of the roof.
Pisa's Cathedral was consecrated in 1118 by Pope Gelasio II, however its construction finished only around the middle of the 12^th century.
A few years after the consecration, the new architect Rainaldo made some changes to the original plan: the front part of the building was lengthened with the addition of three spans in the central nave and a new façade was designed, which foresaw the inclusion (realised later) of the original motive of the overlapping loggias that was particularly successful in the Romanic period in Tuscany (beside the resumption of this motive in the neighbouring buildings of the Baptistery and the Steeple, one should think about the façade of Saint Paul's Church in Ripa d'Arno, consecrated in 1148, and S. Michele in Foro Church in Lucca, which was started in 1143, and S.Martino's Cathedral, made by Guidetto in 1204).
The façade was completed by the sculptor Guglielmo, author of the two pulpits made for the Cathedral between 1159 and 1162, but taken to Cagliari's Cathedral in 1313 to leave room for the new monumental pulpit of Giovanni Pisano.
The sculptor, son of Nicola Pisano, was active in the building yard of the Cathedral (where he also made a half reproduction of the Madonna with Child, previously located in the lunette of a gate of the transept, now in the Opera Museum) and the Baptistery.
Among the important works of art that are inside the Cathedral of Pisa, only to mention a few examples, there are the so-called "Bronze gate of St.Ranieri" made by the sculptor Bonanno Pisano, visible along the outside part of the Southern transept (the gate made by the same artist for the façade in 1179 has been lost), the tomb of Arrigo VII made by the sculptor Tino di Camaino, the mosaic in the apses of the 14^th century (the drawing of St. Giovanni was made by Cimabue), beside the frescoes and the paintings of artists of the 16^th, 17^th and 18^th centuries (Andrea del Sarto, Beccafumi, Sodoma, Francesco Mancini, Placido Costanzi, etc….).