I find this fascinating:

“For the Commedia Dante invented a rhyme scheme known as terza rima (tertiary rhyme: aba bcb cdc) thus continuing to display his fascination with the number three, which was so much on his mind when he was composing the Vita nuova many years earlier.  And each canto is divided into three-line stanzas called terzine, or tercets, in which the the first and third lines rhyme, while the middle or second lines rhyme with the first and third of the next terzina.  The basic metrical unit of the verse is the hendecasyllabic line, quite common in Italian poetry: it is an eleven-syllable line in which the accent falls on the tenth syllable”. 

Sheer genius when considering the Commedia is composed of 14,233 lines.