Ciao Joango,
I see you posted your reply on a new thread, so I'm copying and pasting that on here so it makes it easier to keep the entire conversation in one single place.
Great to know everyone in the family is an adult, makes it easier to also recommend activities like wine tastings

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Tuscany is definitely a region that you can best enjoy driving around and visiting the many small towns you pass through, so let's assume you can have the full 12 days and this is what I'd recommend:
- divide the time staying in 2 places, one in northern area, the second in the southern part of the region. Just makes it less driving as you concentrate on areas closer to where you are staying. Actually, you could do 3 bases, if you want to do an overnight in Cinque Terre.
- easiest would be to fly into
Pisa international airport, Galileo Galilei. That way you can rent the car/minivan there directly. Minivan would give you more space and make it more comfortable to explore.
- if you want to avoid too many crowds, then definitely the later you come the more likely there should be less people. As far as the weather, October should still be pretty good weather, with maybe some rainy days but not many.
- as far as museums, there are a lot with ART! so if you're not interested too much in the history of art, you might not seek the museums out, you will still end up seeing LOTS as you visit churches in the area. Every single piece of artwork seems to have been created for churches, they are now in museums, but many works still remain in the churches. So you might not need to visit any museums at all and still get to experience lots of the history and art of the region.
If you arrive in Pisa, you could definitely visit Cinque Terre in this first part. You could do it first, that way you could actually stay in one of the towns (I recommend Monterosso al Mare) for a night or two, then head back and stay at your second base. Cinque Terre is best explored on foot or by train, so once you arrive, you won't be using the car. Roads are curvy and narrow there, so you don't want to drive - explore the towns by walking.
After Cinque Terre, head back down to Lucca. I would suggest staying in this area as your base. From Lucca you can visit Pisa, the coast around Viareggio, down to San Gimignano and to Florence. You can spend a day exploring the towns in Chianti. Head down to Siena, stopping at Monteriggioni. Overall, I would say 5 days here.
Then move on to the area south of Siena for your secondary base. From there, spend time in Montepulciano, Pienza, San Quirico d'Orcia, Bagno Vignoni and Montalcino. You can easily spend 2 full days exploring these. You can also head toward Arezzo and Cortona on another day. You can spend a day at the outdoor hot springs in either Bagno Vignoni or at San Filippo. If you didn't get to Siena before, you can also go visit Siena... or go back!
As far as the ex-Yogoslavian countries, I have no experience in that area so cannot offer any recommendations. I know lots of Italians love Croatia for the lakes and beaches but that might not be what you're interested in.
Hope these suggestions are useful! Let me know of any other questions you may still have, I'll do my best to help

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