It is about 4-5 hrs from Zurich to Milano by car, but not a difficult drive... as long as the San Gottardo tunnel is open. A few years ago a fire shut it down for several weeks and ealier this year a rock slide on one of the approaches did the same. (Alternate route is the San Bernardino tunnel/pass to the east, but as it's quite a detour, you need to know before you leave ZRH.)

The scenery along the way is spectacular, and as you will be travelling with kids, you may want to stop along the way to take in some of the sites. I recommend the town of Bellinzona (about 3 hrs S of ZRH), the capitale of the Cantone del Ticino. Depending on the age of your kids, they may enjoy the three castles protecting the city including the Castlegrande which is accessible on foot (or elevator) from the main parking lot.

Keep in mind in southern Switzerland and northern Italy, especially in the smaller towns, that most shops close at lunch time (usually 12h00 to 14h00). Conversely, most restauarants are only open at these times. The exception is convenience shops at train stations and highway petrol stations.

Enjoy your trip!
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