Advice on Itinerary and transportation

Hello,
A car or no car makes a big different in some regions.
1-Dolomites, yes you could do a day trip(need a car for that day) to go for one hike, let's say Tre Cime Di lavaredo, it is spectacular. But honestly if you like outdoors, the Dolomites deserves more than one day trip. But this changes the approach and the composition of your different stops.
Another day trip could certainly be Verone. I would keep 2-3 full days for Venice, using one to see Burano and Murano.
2-Day trips from Rome can certainly be Ostia Antica, spectacular ruins that reminds people a bit of Pompei. Easy to get to by taking the train from Pyramid station.
3-The other one could be some sort of an organised tour to see Tivoli's Villa D'este(spectacular palace and gardens dating from the 16th century), and Villa Hadriana, ruins from a huge roman villa(it's almost a small village, this is how big it is)that was built by emporor Adrian in the second century.
As far as train versus Car, I can't comment as always had a car in Italy

Spare the threat of ridiculous tickets, take tours or the train.
Your itinerary looks pretty good. Not sure I would use Venice to do day trips to the Dolomites.

Claude C. Thank you for your thoughts. Would you suggest I skip the Dolomites and perhaps visit them in more depth at another time? Or do you see somewhere in my itinerary where I could make adjustments?

Geovagriffith,
Are you referring to traffic tickets? Also, is there a better jumping off point to visit Dolomites or is that a place that should be a designated destination all on its own?

Maybe you could add time to the Lakes (even possibly instead of Milan) or to Cinque Terre to give you more nature time--but you should get plenty of that in Croatia.
As it reads now, you would not have any need for a car. For train tickets, purchase point to point, no pass.

I guess I would, but then you'll need to find other things to visit while you're in the northern part. Could be part of France, Slovenia(which we really enjoyed), etc
-Since I usually have a car, I assume you checked that you can easily go by bus or something from Milan to Varenna?
I haven't been to Milan, so I'll let others comment. I know you need to reserve Last Supper in advance, and it's not downtown close to the Duomo.
In Tuscany, again, had a car the 2 times we went. I feel a car is a great addition especially in Tuscany, if you want to see some of the fantastic hilltop towns, such as Montepulciano Pienza, Volterra, etc. But again this changes the stops around. For instance leave from Milan, go to Cinqueterre. Leave from there, see Pisa on your way to Florence. From Florence stay 3 days let's say, leave, go to Volterra/San Gimignano on your way maybe and find a home close to Siena for 3 days. From there see Sienna one day, Montepulciano-Pienza or Montalcino(and Sant'antimo abbey) the other 3 days, leave from there go directly to Rome and leave the car, or on your way, stop at fantastic Orvieto to see the village and amazing cathedral.
If it's train and bus only, I'll let others pinch in and provide more info as I'm not familiar

From Venice this would be a delightful day tour.

https://www.venetoinside.com/tours-activities-in-veneto/tour/burchiello-cruise-among-brenta-riviera-villas/

From Florence there are many day trips by train, Lucca, Pistoia, Montecatini Terme/Alto, Bologna,
Viareggio combines nicely with Pisa.
There are also Day tours that will get you out into Tuscany.

https://www.getyourguide.com/s/?q=Florence&et=7679&utm_force=0

https://www.walksofitaly.com/florence-tours/tuscany-day-trips-from-florence/

http://www.toursbyroberto.com

From Rome, Villa d' Este, Orvieto and a pretty village on the beach at Sperlunga.

For train tickets, point to point tickets in Italy are less expensive than a pass. By purchasing early you can get some great reductions with super economy and economy tickets. Use this for looking up and purchasing. There is a schedule change the second week in June, so all tickets may not be showing. To look at the connections now, simply use the day of the week you'll travel
Applying those days to next week.
https://www.trenitalia.com/en.htmlE Italian names. Venice/Venezia S.Lucia. Florence/Firenze SM Novella. Rome/Roma Termini
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