Fiumicino (FCO) is the largest international airport in Italy. It is the recommended option to fly into Rome then take a 1.5 hour train up to Florence.

Florence Airport (FLR), formally named Amerigo Vespucci Airport, is a smaller international airport located closest to Florence.

The fastest way to travel from Rome to Florence is by train. You can first take the Leonardo Express train to Rome's "Roma Termini" station then Trenitalia's "Frecciarossa" high-speed train to Firenze's Santa Maria Novella Station.