Santa Maria Nuova and its secret underground.
S. Maria Nuova is the oldest hospital of Florence. It was founded by Folco Portinari, Beatrice's father, the woman Dante loved for the rest of his life. Obviously today it hasn't got the same aspect as it had in the XIII century. The porch you can noticed from Via S. Egidio was built in the XVII century by Giulio Parigi.
According to the tradition Monna Tessa, Folco's housekeeper, was at the head of a group of women called "Oblate" who offered their life to help sick people.
If you look carefully in the square in front of the hospital you will notice an opening on the ground. The hole is covered with a long and narrow grating: a secret passage hides below it and it still joins the hospital with the convent where the Oblate lived. It's a long gallery: women crossed it to arrive inside the hospital, nobody could see them because they assisted sick people for charity.
Even the great artist Leonardo da Vinci studied anatomy and dissected bodies in this long corridor!!
The cathedral hides a treasure: the archaeological area.
The artist drew even his self-portrait depicting the attitude of an imprisoned man.
It's a little bit strange because the Cathedral and the three doors too are entirely dedicated to the Virgin Mary.
In 1632 the scientist published his "Discorso sui massimi sistemi" and he risked to be burnt at the stake