The iconic Leaning Tower of Pisa is only an hour train ride from Florence so it is a definite day trip must! Pisa is a very small town and you can do this in a day, or just a few hours like I did.
We ate dinner at a place called Pizzeria Trattoria Toscana right across from the leaning tower and it was absolutely amazing! Slightly touristy but we wanted to stay close to the tower. Very good- if you go, you have to try it!