I am wondering if we caught the first train to Milan from CT, would we have time to just see the Last Supper, then get to Varenna on Lake Como in time for Dinner?
Well, we aren't going until next May, so I am hoping it won't be as crowded. How far in advance do I need to make that reservation?
All of the trains from the CT to Varenna will go through Milan. It's a 4.5 hour to 5.5 hour jouney depending on hour many train changes you have. It seems that you could easily get off in Milan for several hours, jump back on a later train to Varenna. When you buy your tickets, you will get 2 or 3 depending on train changes. The train from Milan to Varenna is a regional (local) in almost all cases so you have no seat reservations to worry about. Thus, you could get off the train at Milan and jump back on a later train with the same ticket. Just make sure you validate it just before you get on. From the CT to Milan, you could pick up an ICPlus train which would require seat reservations.
Too much for one day. Varenna deserves to be seen when you are relaxed and in a good mood and ready to b captivated by the Lake. The hectic pace you describe would not do. We would recommend you do separate day trips from Milan- one to CT and the other to Varenna.
Better yet, skip CT and spend the time in Varenna!!!!