The dome of the Cathedral of Santa Maria del Fiore in Florence, Italy, was completed in 1436. Its supple curves and innovative engineering are a monument to the genius of Filippo Brunelleschi.

Over two years, this work was performed with precision in the cathedral’s silent, cavernous interior, where harmonization was achieved entirely by ear. Now, the organ’s grandeur is unmistakable.

Visitors like to joke that the cathedral was designed inside-out: its exterior boasts intricate designs and breathtaking features while the interior ... to the top of the dome (the cupola) where ...