REBECCAC84: I know a challenge when I see one, go find that tomb!
The first great basilica in Florence, Santa Maria Novella was consecrated in 1420 despite being unfinished. The famous humanist Leone Battista Alberti designed the upper façade, completing the church in 1470.
However, Santa Maria Novella’s origins extend back before the Crusades to an ancient oratory, located on the same site, with a hidden tomb underneath. As of today, the tomb has not been uncovered.
On a related note, one of my favorite quotes is located inside the basilica, written on the image of a tomb: “I was once what you are, and what I am you will become”.