Italy - Switerland - and ??? 8 days with teens (3 girls 13,16, 22) Go....

I am taking a giant leap, here, and choosing to believe that this is a serious question. But I'm having a really hard time thinking it really is. If you are for real, emaraegarcia, please come back with more information about arrival city, departure city, and what you all want to do, and do some quick homework on distances. Choose one country, maybe, with the time that you have, which is 10 nights on the ground. I don't think any regular poster on this forum would ever imagine 2 days per country, and dragging teenagers with you on that venture. Take a look at Rick Steves' book "Europe Through the Back Door" as a starting point.

Your time is short and very few people on this forum would try to fit in 3 countries in a week, or perhaps 10 days. Rather than naming whole countries, there must be specific cities that are of most interest to you. For instance, you could fly into Venice, train from there to Luzern, train to Paris, and then fly home. Those are not unusual travel distances, but also not short. Choosing three cities just in Italy, for instance would mean less time and money spent on transportation.

First, your trip is 13 days, 11 nights. Where are you spending the other 5 nights?
Second where are you flying in and out of?
Third it would be a death March to try and do 3 countries in six days. You'd see only various forms of transportation.

Pick only one other country, preferably one other city, that has opportunities for day trips to spend the last 5-6 nights.

Scythian makes a good point on his Lucern/Milan path, but split them to 3 days each.

While Milan may be closer to Lucerne than to Rome, it takes (a bit) less time to get to Rome by train. Certainly the travel time to Lucerne is not an impediment, but I would question any friend's travel plan of a trip to Italy and Switzerland if he told me his sole destination in Italy was Milan.

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3 day in two places