Both choices sound wonderful and take a full day so combining is not an option. Anyone been to either location? Thoughts?
Have not been to Cesky Krumlov but Salzburg is delightful, especially if you are fond of Mozart and/or the Sound of Music
I concur with sherry_schare. If you enjoy classical music Salzburg will not disappoint. The old city - Alstadt - is lovely for strolling. You can also take the funicular to the fortress for great views, but I don't know if Tauck offers that. Can't help you with Cesky Krumlov.
Cesky Krumlov is a beautiful town, the best thing is if you could do both, do you have a pre stay where that may be possible?
Cesky Krumlov is delightful but possibly worth half a day in my opinion. For a full day, I would opt for Salzburg.
We did both on our east-bound tour. We had a 1 1/2 day pre stay in Prague, so toured the Jewish quarter with a private guide after we arrived (toured “old town” with Tauck on Day 2). We got an early start with same guide on Day 1, went to Cesky Krumlov, got back about an hour before the Welcome Dinner.
I’m doing what Alan does!!