Cathedral

The heart of the Piazza del Duomo is the Duomo, the medieval cathedral of the Archdiocese of Pisa, dedicated to Santa Maria Assunta (St. Mary of the Assumption). The cathedral has two aisles on either side of the nave. The transept consists of three aisles. The church is known also as the Primatial, the archbishop of Pisa being a Primate since 1092.

Its construction began in 1064 by the architect Buscheto. It set the model for the distinctive Pisan Romanesque style of architecture. The mosaics of the interior, as well as the pointed arches, show a strong Byzantine influence.

The façade, of grey marble and white stone set with discs of coloured marble, was built by a master named Rainaldo, as indicated by an inscription above the middle door: Rainaldus prudens operator.

The massive bronze main doors were made in the workshops of Giambologna, replacing the original doors destroyed in a fire in 1595. The original central door was of bronze, made around 1180 by Bonanno Pisano, while the other two were probably of wood. However, worshippers have never used the façade doors to enter, instead entering by way of the Porta di San Ranieri (St. Ranieri's Door), in front of the Leaning Tower, built around 1180 by Bonanno Pisano.

Above the doors are four rows of open galleries with, on top, statues of Madonna with Child and, on the corners, the Four evangelists.

Also in the façade is found the tomb of Buscheto (on the left side) and an inscription about the foundation of the Cathedral and the victorious battle against the Saracens.

At the east end of the exterior, high on a column rising from the gable, is a modern replica of the Pisa Griffin, the largest Islamic metal sculpture known, the original of which was placed there probably in the 11th or 12th century, and is now in the Cathedral Museum.

The interior is faced with black and white marble and has a gilded ceiling and a frescoed dome. It was largely redecorated after a fire in 1595, which destroyed most of the Renaissance art works.

Fortunately, the impressive mosaic of Christ in Majesty, in the apse, flanked by the Blessed Virgin and St. John the Evangelist, survived the fire. It evokes the mosaics in the church of Monreale, Sicily. Although it is said that the mosaic was done by Cimabue, only the head of St. John was done by the artist in 1302, his last work, since he died in Pisa the same year. The cupola, at the intersection of the nave and transept, was decorated by Riminaldi showing the assumption of the Blessed Virgin.

Galileo is believed to have formulated his theory about the movement of a pendulum by watching the swinging of the incense lamp (not the present one) hanging from the ceiling of the nave. That lamp, smaller and simpler than the present one, is now kept in the Camposanto, in the Aulla chapel.

The granite Corinthian columns between the nave and the aisle came originally from the mosque of Palermo, captured by the Pisans in 1063.

The coffer ceiling of the nave was replaced after the fire of 1595. The present gold-decorated ceiling carries the coat of arms of the Medici.

The elaborately carved pulpit (1302–1310), which also survived the fire, was made by Giovanni Pisano, a masterwork of medieval sculpture. Having been packed away during the redecoration, it was not rediscovered and restored until 1926. The pulpit is supported by plain columns (two of which are mounted on lion's sculptures) on one side and by caryatids and a telamon on the other: the latter represent St. Michael, the Evangelists, the four cardinal virtues flanking the Church, and a bold, naturalistic depiction of a naked Hercules. A central plinth with the liberal arts supports the four theological virtues.

The present-day pulpit is a reconstruction of the original. It does not lie in its original position, which was nearer the main altar, and the columns and panels are not original. The original stairs (perhaps of marble) were lost.

The upper part has nine narrative panels showing scenes from the New Testament, carved in white marble with a chiaroscuro effect and separated by figures of prophets: the Annunciation, the Massacre of the Innocents, the Nativity, Adoration of the Magi, the Flight into Egypt, the Crucifixion, and two panels of the Last Judgement.

The church also contains the bones of St. Ranieri, Pisa's patron saint, and the tomb of Holy Roman Emperor Henry VII, carved by Tino da Camaino in 1315. That tomb, originally in the apse just behind the main altar, was disassembled and moved many times over the centuries for political reasons. While the sarcophagus is still in the Cathedral, some of the statues were put in the Camposanto or in the top of the church's façade. The original statues are now in the Museum of the Opera del Duomo.

Pope Gregory VIII was also buried in the cathedral. The fire of 1595 destroyed his tomb.

The Cathedral has a prominent role in determining the beginning of the Pisan New Year. Between the tenth century and 1749, when the Tuscan calendar was reformed, Pisa used its own calendar, in which the first day of the year was March 25, the feast day of the Annunciation of Mary. Years were counted such that the Pisan New Year begins 9 months before the ordinary one. The exact moment is determined by a ray of sun that, through a window on the left side, falls on an egg-shaped marble, just above the pulpit by Giovanni Pisano; this occurs at noon.

Some relics brought back during the Crusades can also be found in the Cathedral: alleged remains of three Saints (Abibo, Gamaliel, and Nicodemus), and a vase that is said to be one of the jars of Cana.

source https://en.wikipedia.org/wiki/Piazza_dei_Miracoli#Duomo