Which 3 Cities to Visit in December

It would be meaningful to add interests to get good advice. Towns with lower distance (train travel) are Dresden, Regensburg, and with a little more travel distance Nuremberg or Berlin.

Naaaa, simple question. BUDAPEST. One trip 3 cultures. Can't go wrong.

Have you booked your flights? Into and out of where? What’s your travel experience? That information will help determine other city visits.
Without any other information, my choice would be either Berlin or Vienna which is a bit far.

Budapest: nice destination but isn't in Germany or even that close...

Normally I'd suggest Nuremberg, but it can be overcrowded - and overpriced - on those December weekends thanks to the huge Christmas Market crowds.

So I think Würzburg could be a great choice. W'burg is in northern Bavaria, but it's a stronghold for Franconian culture - lots of local food specialties and an emphasis on wine. The city makes for a nice contrast with Munich for sure, and it's close to other great Franconian destinations if you wished to do an outing or two; Bamberg, Rothenburg ob der Tauber, and Nuremberg are among the most popular day trips and easily done by train from W'burg.

https://www.tripadvisor.com/Attractions-g187321-Activities-oa0-Wurzburg_Lower_Franconia_Franconia_Bavaria.html

https://www.tripadvisor.com/Collections-e5uOn0xc1iPfcX4QzQGAEza.html

From Munich, Würzburg is 2 hours away by direct train. If you wished to fly home out of FRA, that airport is just 1.5 hours from W'burg by direct train.

Do you want to stay near Munich? Would Salzburg be too far? What about Garmisch, where there might be snow? Do you want a smaller town, like Oberammergau? Stuttgart with the near-by town of Esslingen might be nice.

One trip 3 cultures.

Germany has a huge cultural variety in different regions, so no need to travel longer distances for this reason. Nothing against Hungary or Budapest in general.

Both Munich and Nuremberg are easy to get to from Prague by train. Between Prague and Munich your best known, big, market is Regensburg. But there are a lot of other ones. Two I'll highly recommend, smaller, but very few Americans even know about; Amberg, and Pilsen. You want to be someplace different? These are beautiful and very overlooked.

Rus, Mark: every time you guys start the nationalist chatter i get nervous. Just kidding. But seriously, a great Christmas tour for me would be some place in Germany for the recognition of origin, Vienna for the opulence and Budapest for the lifestyle. But thats very subjective based on my interests and what moves me.

Athough I would stay in Rothenburg, Russ’ choice of Wurzburg is a good one