Brunelleschi's Dome & the Cathedral of Santa Maria del Fiore

Why is it significant?

Find a spot on the south side of the cathedral, step back as far as the crowds allow, and let your eyes climb. Above the striped marble walls rises an eight-sided drum, and above that the great red dome, ribbed in white, sitting on the city like a hen on her eggs.

Key Facts

Open the walk

Find a spot on the south side of the cathedral, step back as far as the crowds allow, and let your eyes climb. Above the striped marble walls rises an eight-sided drum, and above that the great red dome, ribbed in white, sitting on the city like a hen on her eggs.

When work on this cathedral began in 1296, the plan already called for an enormous octagonal dome. The trouble was that nobody knew how to build one. For decades the church grew around a gaping hole more than forty metres across, open to the sky. The usual method, a wooden frame to hold the vault up while the mortar set, would have swallowed whole forests. In 1418 the city held another competition, and this time Filippo Brunelleschi, the loser of the Baptistery doors, did not lose.

His solution was outrageous: no supporting frame at all. He built two shells, an inner and an outer one, with stairs running between them, and laid the bricks in a herringbone pattern so that each ring locked itself in place as it rose. He invented an ox-driven hoist that could lift loads and lower them again without the oxen ever having to turn round. Millions of bricks went up. The city even made Ghiberti his co-supervisor, and the story goes that Brunelleschi simply took to his bed, pretending to be ill, until everyone saw that work stopped without him.

The dome was consecrated by Pope Eugene the Fourth on the 25th of March 1436, which in those days was New Year's Day in Florence. Brunelleschi died ten years later, just as the lantern on top was started. The gilded ball crowning it was made in Verrocchio's workshop, where a young apprentice called Leonardo da Vinci was learning his trade. Around 1600 lightning knocked the ball down, and a round marble slab in the paving behind the apse is said to mark where it fell.

Now glance at the slender bell tower next to the facade. Giotto designed it and began it in 1334, but he died three years later having built only the lowest level, and others finished it. The marble front of the cathedral, by the way, is not medieval at all; it was completed in 1887. Follow the flank of the church round the apse to the far side of the square, where the workshop that built all this still keeps its treasures.