Which city is the best for Christmas Markets?

Vienna or Salzburg in Austria.

Nuremberg
http://www.christkindlesmarkt.de/english/

Every city has a good Christmas market it seems - Frankfurt too has an especially large one.

Dresden

This website has a listing of what seems like all of them.

http://tinyurl.com/3zlpq

Have fun!

We like Munich and Nuremberg. They all have a lot of the same stuff and frequent Gluhwein stands but some of the small ones have their own charm, Rothenburg is fun although not nearly as big as those in the cities.

Dresden or Nürnberg

Our favorite was Muenster, although I would love to visit Dresden's this winter. Muenster's market had very few tourists, most of the items for sale were very good quality.
Baden-Baden's market was much better in 2006 than it was in 2005 (and 2004); it's in a very attractive setting with live music most days. And of course you have the spa town to wander through. Some of the small towns in the Black Forest have wonderful markets.
The only Christmas market that I didn't like was Aachen's--a mob scene, a lot of junky stuff, and it seemed like most people were there just to get drunk. Not quite the holiday spirit we were looking for.
Wherever you go in Germany, you're sure to find a good Christmas market somewhere nearby.

We liked Munich's (including the one market dedicated just to Christmas creches) and also the three different markets in Regensburg.

My favorlites are Michelstadt and Bad Wimpfen. they are more like family reunions or county fairs than the Euro/tourist driven markets in the larger cities. If you are there to shop, try the larger cities. If you are there to understand a bit about the role of the markets in German life or simply enjoy being a part of a happy celebration, try the smaller towns [however not Rothenburg ODT]

We were in Munich, Nuremburg, and Rottenberg this past December. Nuremburg is one of the oldest and is famous for its gingerbread (at least 20% nuts) and wurst (small finger-size sausages that are especially delicious straight from the grill at the outdoor markets!). Rottenberg's was small, but charming. Munich's was large and festive.

Correction to my post: Dresden not recommended this year. Construction works on the Altmarkt square are the reason for a re-location of the main Christmas Market. It's going to take place in a very little charming surrounding.

We loved the markets in Heidelberg.

We've had the good fortune to attend them in Dresden, Frankfurt, Nuremburg, Munich, Naumberg, Annaberg-Bucholz (sp), Rothenburg, Trier, Brussels, Freiburg, Regensburg, Prague, Sailauf (my grandmother's town), Vienna and some my family took us to that are unknown to me.

I didn't go to all on one trip as we prefer to travel in Nov/Dec to optimize Thnksgiving days off with work days off.

I agree with weber6560 - they each have their charm but it depends on what you want to get out of it. History seems to favor Dresden and Nuremburg; size can go to Munich, Nurmeburg and Brussels; plain ol' drinking and shopping - all of them - although Vienna offered a hot whisky-type drink.

Our favorites: Nuremburg (size and history), Annaberg-Bucholz (small town in eastern Germany with either no tourists or quiet ones) and Sailauf (where everyone knew everyone and was an extension of your living room but held on one weekend from 1-7!)

Least favorite: Brussels