from Varenna (lake Como) to St. Moritz

Yes. First, you take the Italian Regionale train from Varenna-Esino to Tirano which is on the border of Italy and Switzerland. Second, you take one of Switzerland's most scenic train runs (the Bernina Express) to St. Moritz. You can see all of the runs on www.trenitalia.com and www.sbb.ch/en. On the Swiss website, you want the "D" train.

Larry...thank you so much. This solves a problem for me. My sister wanted to stay in Como, I in Varenna....you helped me win!