Today, Pisa is a moderately sized university city, famous for being the birthplace of Galileo and for its leaning tower. But a thousand years ago, it was a powerful maritime republic, achieving glory by crushing the spread of the Saracens in the Mediterranean.

At the end of the 11th century, the Pisan navy supplied the transport for the First Crusade, which, in turn, led to the acquisition of colonies, increased trade and the receipt of Corsica as a gift from the Pope. Pisa's military supremacy, however, was soon challenged, firstly by Genoa and then by Florence. By the beginning of the 14th century, its days as a major power were but a distant memory. 

But the fruits of Pisa's golden age live on in four extraordinary buildings, which, together, make up the Piazza del Duomo, also known as the Piazza dei Miracoli, one of the most remarkable architectural ensembles in Italy. The piazza comprises, in order of building, the Cathedral, the Baptistery, the Bell Tower and the Camposanto (cemetery).

Begun in 1063 by an architect named Buschetto di Giovanni Guidice, (whose sepulchre can be seen on the left of the facade), Pisa's Cathedral was funded by the spoils captured in its maritime war with the Saracens. It was completed a century later and is one of the most celebrated buildings in the Pisan Romanesque style. The interior with its black and white decoration recalls the Moorish architecture of Cordoba in Spain.

The cathedral boasts an ancient set of bronze doors, which were created at the end of the 12th century by Bonanno Pisano. Dedicated to Pisa's patron saint, San Ranieri, they can be found, facing the campanile, at the back of the building. 

But, perhaps, the cathedral's most prized work of art is is pulpit, which was carved by Giovanni Pisano between 1302 and 1311. It is a work of astonishing virtuosity; the carved figures seem almost freed from the block. Giovanni was the son of Nicola Pisano, who carved a pulpit for the Baptistery (see below). Giovanni's pulpit is held to be the more ambitious of the two, in terms of its figure sculptures. 

A curious mix of the Gothic and Romanesque, the Baptistery, which happens to be the largest in Italy, is circular rather than octagonal in from. It was begun in 1152 by an architect known as ‘Diotisalvi’ [God saves you], whose name can be seen on the column to the left side of the door. Lack of money brought building to a halt and when work restarted architectural styles had changed from the Romanesque to the Gothic.  The plainness of the interior contrasts strongly with the decoration of the outside. It is home to a revolutionary piece of sculpture by Nicola Pisano.

The pulpit is dated 1260 and was Pisano’s first major commission. It marks a return to the spirit of classical antiquity prefiguring the Renaissance in nearby Florence by more than a century. The conventional format for a pulpit had been invented a century before and consisted of a rectangular balcony raised on columns and abutting a wall with narrative reliefs ranged along the sides. Nicola’s pulpit is a new departure from this model. It is freestanding and hexagonal in shape with a single, large panel, carved in relief, on each of the sides. The platform is supported on round arches.

In 1173, work began on the third component of the Piazza dei Miracoli and the one which would make Pisa famous the world over, namely, the campanile or bell tower. Although we know the name of the architects who were responsible for the three other buildings in the piazza, we have no idea who designed Pisa's most famous monument.

By 1178 the tower was almost half built when suddenly work stopped. We don't know the reason for this, but work would not restart on the bell tower for almost a century. In 1272, after ninety-eight years of inactivity, work was finally resumed.

The man in charge, Giovanni di Simone, found the tower already tilting to the south. Six years later the tower was on the threshold of being completed when work was again halted. All that remained to be built was the belfry, but the tower was still leaning. In 1298 a commission was convened to investigate the tower's tilt. Unfortunately, we have no record of what they discovered or how they reacted.

Fifty or so years later the belfry was added and in 1370, almost two centuries after work first started, the campanile was completed. Its inclination measured 1.6 degrees from the vertical. Over the next six hundred years this would slowly increase until, at the end of the last century, the tower inclined almost 5 metres from the perpendicular. It was calculated that it was leaning at a rate of 1mm per year and that if nothing were done, it would collapse in 2040.

At this point the tower was closed to the public and subjected to years of major engineering work. In 2001, one of the world's most famous buildings was finally re-opened to the public.

For an entertaining account of the history of the bell tower, see 'Tilt: The Skewed Tale of the Tower of Pisa' by Nicolas Shrady.

The fourth component of the Piazza dei Miracoli is the monumental cemetery or Camposanto, which was begun by Giovanni di Simone in 1278, but only completed in the 15th century. According to legend, Pisa's Archbishop [1108-1178] brought shiploads of earth from the Holy Land to form a burial ground here. 

It was decorated with frescoes in the 14th and 15th centuries by artists such as Taddeo Gaddi, Andrea Bonaiuti, Spinello Aretino and Benozzo Gozzoli.

All the frescoes were severely damaged in 1944 when the roof fell in following a bombardment of the city by the allied forces bombed Pisa. The frescoes were detached and the sinopia (the preliminary sketches beneath the frescoes) were preserved in a museum devoted to such works.