Early Return Flight - Rome Travel time

Well, hiring a car would cost a fortune I think. It's 243 Km, around 120 miles. I am famously cheap...and I've had to catch the Cotral bus at 1 am in Rome to get to the airport. If it were me, I would take an early train a day early and stay at a hotel near Termini, the main train station. There are multiple ways to get to the airport from Termini. Find a good hotel using Tripadvisor. Check out deals on Kayak.com or contact the hotel directly. If you're staying in Siena for a long time (you don't mention of you're staying for a week, a month, a year...) then you might want to leave an extra day early and spend a couple days in Rome. My favorite restaurant is Vecchia Roma, in the Pantheon area.

There is always one big question is it a direct flight back to the US or a domestic fight connect to somewhere else in Europe for the direct flight back? If a direct flight you need to be in the airport no later than 9 to 9:30 AM. If a connecting flight, then you can be a little later around 10. For our quick overnight stays in Rome we use Hotel Contilla basic three star hotel with so/so morning breakfast BUT just one street south of Termini out the door on the south side of the station. That is the left side as you exist Termini with the tracks to your back.

I'd agree NOT to try and make your flight from Siena on your day of departure. If things don't go right, you could be stuck. I'd agree that you'd be better served to come back the day before. With an 11:50 AM departure you can use all "options" to get to the airport. And of course, it you come back early, you get to spend ANOTHER night in Rome and see sights like this!

Thanks for your help. We have decided to stay in Rome the night before we depart. Thanks for the hotel reccomendatiob too.