Florence's 
Duomo, its cathedral, and particularly its great dome, dominate the city's skyline and identity like no other great city and great building. The green, white and pink marble Gothic building was erected in the 14th century--anticipating the largest dome that ever had been built--but without the engineering nor architectual expertise to complete such an endeavor. But in 1420, Brunelleschi solved these problems, studying the Pantheon in Rome, drilling into its dome to see how the Romans had done it a millennium earlier. He solved the problem and many underlying engineering problems: one of the earliest patents granted was for the special hoists he designed to lift 3 ton blocks into the sky, along with thousands and thousands of bricks, all resting on a complex system of arches and buttresses and a double-dome. It's been standing up there for nearly 600 years, I know, but I am always nervous in these ancient and gigantic buildings that are held together by nothing much more than friction and gravity. And genius.
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The Duomo, from Piazzale Michaelangelo, across the river 
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Speaking of genius: here is the campanile, the 
bell tower, built a bit earlier; 267 feet tall; 
designed by Giotto, aka "Father of the 
Renaissance," in painting at least; but he also 
did campaniles, bridges...one begins to  
understand what being a "Renaissance Man" 
was all about... 
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Ground-up view 
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West facade and campanile 
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Intitially, the interior looks rather stark, if huge (3rd largest 
nave in Christendom) 
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But then when one begins looking around,  
there are all kinds of interesting things:  
e.g., this giant bass-ackwards 24 hour clock  
in Roman numerals 
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Super-billboard-sized illusionistic paintings of 
local equestrian heroes 
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Great glass, and 
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This merely billboard-sized painting of Dante explaining 
his Divine Comedy to the Florentines; he was subsequently 
exiled and died in Ravenna, but Florence would really like 
to have his mortal remains back now 
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And then the KO punch: the interior of the great dome is just 
as colossal and impressive as the dome itself...Vasari's Last 
Judgment 
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Great Hell and Satan scenes 
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But best of all, at the very top, hanging in over the edge, 
this motley crew of illlusionistic skumdullions lightening 
things up a bit... 
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Glimpse of a Last Supper behind the altar 
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And beautiful della Robbias all around 
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