Traveling to Siena for the new year; weather? attractions? trains?

My husband and I will be traveling to Siena, Italy, for a week, starting on New Year's Eve. We will be making some excursions to Florence, Venice and Rome. I would appreciate insight regarding train travel (for example, is Trenitalia part of Eurail, or do you purchase tickets separately?), bus travel (better, worse than the trains?) the weather (what is the climate like in winter; will I need a warm coat, layers?) and attractions (as it won't be peak tourist season, will some attractions be closed or open on abbreviated schedules?)...I hope this isn't too much information to pack into one question...but if other travellers or residents have suggestions, recommendations or helpful hints, we're very excited to visit! Thanks--

I have been to Siena during the summer months and Rome in January.

Weather - can be cold - would not expect to be wearing shorts! We took ski jackets and gloves when we went to Rome in January and found that we wore them all bar one day.

Train travel is very good in Italy. You buy your tickets at the station and validate them before boarding the train. The trains in Italy tend to run exactly to time and they do have some double decker ones. Always have been very clean and comfortable to travel by train so have never bothered with anything else.

Sienna is very good for shopping and they have a fabulous square where everyone congregates - next to the statues of Romulus and Remus and the she wolf.

Rome will keep you occupied for days but take good walking shoes! The Zoo you can probably miss out but the historical sites are fantastic. In fact visiting when the weather is cooler is probably much nicer than in the heat of summer! Make sure you give some time to Piazza Navona and the surrounding area on an evening and just take in the ambience

Enjoy the local cuisine and even though it will not be hot - enjoy the gelateri (ice cream!)

Have fun!

Bus travel is ok if you do not need to get anywhere very fast. It is NOT as reliable as the train and would prefer the train, unless you are going to smaller villages. Even with those, often the bus does not go into the center of town, so you must walk a distance. Renting a car can be a good way to go if you feel comfortable. The roads are easy to drive on (outside of Rome) and very much like the USA. If you do this, don't try to save a buck and go with a discount rental company. Go with a name brand. i HIGHLY recommend getting a car. It is FUN to stop at places like Pienza just south of Sienna. Otherwise, you'll miss SO much, staying right in the heart of Tuscany, but not living 'the good life'. the big cities are wonderful, but don't miss a day trip to some hill towns. You can easily visit 2-3 in a day. There are many great choices within 60 minutes of Sienna. Have fun!

Trenitalia is part of Eurai. It is the name of the passenger section of the state RR (FS-Ferrovie del´Estado)
www.trenitalia.it is the homepage.
It is winter, also in Italy. So rather have some warm clothes with you.
Contact the local turist office. They give you all the information you want (and more).
Enjoy your trip!