Built by Filippo Brunelleschi who won the competition for its commission in 1418, the dome is egg-shaped and was made without scaffolding. The raising of this dome, the largest in the world in its time, was no easy architectural feat. At the base of the dome, just above the drum, Baccio d'Agnolobegan adding a balcony in 1507. One of the eight sides was finished by 1515, when someone asked Michelangelo - whose artistic opinion was by this time taken as cardinal law - what he thought of it. The master reportedly scoffed, "It looks like a cricket cage." Work was immediately halted, and to this day the other seven sides remain rough brick!