The Mystery of Florence’s Cathedral Dome

    The Mystery of Florence’s Cathedral Dome

    Florence. For centuries travelers have been coming here to gaze at its architectural wonders. But to the people of Florence in the 1400s the most important building in the world was the Cathedral of Santa Maria del Fiore. There was only one problem though: their beloved cathedral was missing the dome. Their predecessors had begun the church in 1296, but at the time nobody had any idea of how to build a dome for an octagonal floor plan nearly 150 feet wide. So for many decades the winter rain and summer sun had streamed down through the enormous hole in the roof of the cathedral.

    In 1418 a contest for the ideal dome design was announced, with a prize of 200 gold florins. In the end, after many debates and arguments, the dome was built. It was an absolute marvel. A perfect structure. It seemed like the work of God. The construction of the Duomo was so important that it helped start a whole new era of art and engineering. Many believe that Renaissance was ignited by the completion of the dome on the cathedral of Santa Maria del Fiore. But what seemed to be like the work of God was actually the work of a man. His name was Filippo Brunelleschi, an enigmatic figure who was trained as a goldsmith and had no architectural training or experience. Yet he took on what seemed an impossible task.

    Basilica of Santa Maria del Fiore

    Built without the use of freestanding scaffolding, or modern machines the dome is still the largest of its kind in the world. There are many unanswered questions that surround the construction of the Duomo. How could builders work at these great heights? How could 40,000 tons of masonry hold together without collapsing?  Brunelleschi was a very suspicious and secretive man. He left behind no notes, no pictures, no blue prints. Fearing competition, he even refused to explain how he would achieve his goal and nearly six hundred years later nobody knows exactly how he did it. The precision of the construction would be difficult to re-create today, even with the most modern devices.

    The dome is in the shape of a pointed arch with eight sides rising to a central point and crowned by a marble lantern. The exterior tiles conceal walls containing over 4 million bricks and what appears to be a single solid structure is actually two domes, one inside of the other. The interior dome covers a space nearly half the length of a football field, while the exterior wall raises up 10 stories high above the cathedral wall. By using a double-shell design, Brunelleschi made the structure far lighter than a solid dome of this size. He wove  the bricks into a herringbone pattern to give the dome additional solidity.


    Brunelleschi lived to see his masterpiece, but died soon after, on April 15, 1446. He was buried in the crypt of the cathedral. The inscription on his grave reads: “Here lies the body of the great ingenious man Filippo Brunelleschi of Florence”.

    Florence’s greatest pride –Il Duomo–  remains to this day an architectural mystery.