07:35 — Depart Roma Termini
Frecciarossa or Italo; book the early train 2–3 weeks ahead for ~€20.
Ninety-two minutes each way, trains every 15–20 minutes: Florence from Rome is the easiest great-city day trip in Europe. Here is an itinerary that doesn't feel rushed.

Frecciarossa or Italo; book the early train 2–3 weeks ahead for ~€20.
SMN station is 10 minutes on foot from the cathedral. Climb the dome ONLY if you pre-booked.
Two hours is enough for the highlights: Botticelli, Leonardo, Caravaggio.
Cross Ponte Vecchio, eat where the menus are Italian-only.
David, or the gardens if museums are done. Gelato at Vivoli either way.
Trains back to Rome run past 21:30 — no need to sprint.
07:35 — Depart Roma Termini is the strongest single pick — Frecciarossa or Italo; book the early train 2–3 weeks ahead for ~€20.
For high-speed trains, yes — 2–3 weeks ahead for the best fares. Regional trains have fixed prices; buy on the day.
Every trip on this page is chosen specifically because the train (or public transport) does the whole job.