arrival in Rome/secuirty/immigration - time it takes

I'm not positive I understand your question - you want to leave FCO FOR Tiburtina at 10:30? Then, take a bus to somewhere AT 1:45/13:45? I know the trip from Tiburtina to FCO takes about 45m; I'd assume the reverse, too. Assuming in Italy is a dangerous thing. I've never needed to collect luggage at FCO, but it sounds as bad as anywhere and then some. Allow some time. In general, you really should read as much of this website as possible; the info is great, and kept up-to-date: http://www.roninrome.com/transportation/fco-terminal-3-arrivals-area I just chose a page for you concerning FCO Airport; there are many links within his posts that lead to even more great info. His photos are very helpful, too! Also, http://www.roninrome.com/transportation/the-fr1-metropolitan-train-to-and-from-the-fiumicino-fco-airport

Yes, we fly INTO Rome's FCO at 8am and want to get to Tiburtina, because that is where our bus leaves at 10:30 am to go to Siena....unless there is a better suggestion....

Deb, In my experience, the time can vary. In some cases, 2.5 hours will be adequate and in other cases not (this IS Italy, after all). On my 2010 trip, my arrival at FCO and collecting my checked luggage did NOT go well for "reasons beyond my control". Even the staff at Lufthansa didn't seem to know what was happening, and they were very apologetic. My advice would be to "plan for the best" and hope it all goes well, BUT have a backup plan. If you miss the Bus to Siena, find out when the next departure will be OR travel to Siena by train. You could either take the Metro to Termini (direction "Laurentina", four stops) OR take a train directly from Tiburtina. The shortest rail travel time from Tiburtina is ~3H:10M, while from Termini it's ~3H:19M. The trains usually have one change in Chiusi. There are more frequent rail than Bus departures, so that method will probably get you there sooner. As you'll be tired after the long flight, take a Taxi from the rail station in Siena up to the town. Happy travels!

Thanks for the comments on the site Eileen. Deb, assuming you're coming into FCO from the USA, you would have to ride the skytrain in from the G Gates, clear passport control, get your luggage, and then walk over to the FCO Train Station. The fastest way to Tiburtina is to ride the The FR1 Metropolitan. After 08:00, unless you're arriving on a Sunday, it leaves every 15 minutes from FCO. It's about a 48-minute train ride to Tiburtina station and then a 5-minute walk from inside the station to the Siena "bus depot." You can see the exact train departure and arrivals on the Trenitalia website by using the names, Roma Aeroporto and Roma Tiburtina. There you'll discover your last options are the
09:13 train, arriving in Roma Tiburtina at 10:01 and the 09:28 train, arriving at 10:16. Frankly, the latter is just too tight as these trains are often running late... So you would have to be in the station by about 09:05 AM to purchase tickets, validate, and wait for the train arrival. That gives you ONE HOUR to get off the plane, walk to passport control (5-7 minutes), go through passport control at the peak arrival time of the day, get your luggage, and walk 7-10 minutes over to the train station. If you have carry-on only, this is possible. The wild cards will be the number of folks trying to get through passport control and how long you have to wait for your luggage. And of course, all bets are off if your plane is late.

As mentioned by Ken, one hour is an optimistic goal. I've done it in an hour, but I've also often had to wait for luggage 30-40 minutes. As we say here, T.I.I. (This IS Italy!). Often things in Italy don't work the same, or work at all. Yes, it can be done - but I'm not sure I'd start my vacation on this tight a window. Given the train travel and walking times, you have perhaps a 30-40 minute "window of error." In that "window" you'd have to disembark from the plane, clear passport control AND retrieve your luggage. (Carry-on only does increase the odds in your favor). This is why I don't recommend pre-paying for train or bus transport on the date of your arrival. I've had to wait 1.5 hours for luggage off a Delta flight from ATL... so you just never know. And again, if your plane is late, everything gets messed up. Better to wait, have your options printed out, and then make the decision - and the purchase - as you arrive. It may cost you a little more (no Trenitalia MINI promotion for example), but the cost of missing a bus or train with pre-paid tickets is far more. Good Luck!

And don't assume "carry on" is the solution. Airplanes are FULL, overhead bins are fuller. Every week I routinely see "carryon" having to be checked because there just is no more space. So if your plan is "I won't have to wait on luggage" there could be a problem.....