Brunelleschi and the Dome Di Santa Maria del Fiore. At55 meters (180 feet) above ground it would the largest dome built since the
Pantheon in Rome was finished 1500 years before
After most of the cathedral was built in 1296 many builders tried to complete the dome. But none could do it.
No one knew what material to use. Many builders knew how to build concrete dome. However the dome in Florence
needed to be wider than any dome ever built. Also tall buildings of the time relied on structures that supported the heavy
stone from the outside. The cathedral did’t have these structures, so a concrete dome was too heavy. It would easily fall.
So, the cathedral root was left unfinished for over a hundred years.