italy trip

3 nights in each city is the magic number.
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If you spend 2 nights in each city, it gets tiring real quick. Seeing 4 cities in 8 days is exhausting, and seeing 8 cities in 16 days is much worse.
Here is what 2 nights schedule looks like:
Day 1: Transit day, 2PM to 4PM check in.
Day 2: One full day
Day 3: Another transit day (takes 6 hours at least)

Of course spending more than 3 nights in each city is better, but most of us don't have unlimited vacation time and unlimited funds. 3 nights is a good compromise if you want to see as many cities as possible.

How long are you going for?
5 or 6 cities is a lot unless you are going for a month.

Like others said- 5-6 is too ambitious.

My first trip to Italy was roughly this:
Night 1- overnight on plane
Nights 2-4 Rome (Trastavere)
Nights 5-7 Monticchiello (Base for Tuscany)
Night 8 - Rome Airport

We spent a day exploring Rome - Coliseum etc.
A day at the Vatican.
Drove to Monticchiello- stopped in Orvieto.
A day trip to Florence/Siena.
A day driving Tuscany- Montalcino, Montepulciano, etc.
Leaving Tuscany we hit Cortona then back to Rome that evening for an early flight out the next day.

We crammed in as much as we could while still being able to relax and enjoy. If you try to do too much you will not have time to soak it in- which is the entire reason for going.

I have taken a similar cruise. Had a wonderful time on it but I have to say that a cruise is not my favorite way to experience Europe because you don’t spend enough time in port. This is especially true if you want to have dinners in great restaurants which is very important to me when I travel.