Originally Posted by
reuthermonkey
If you're not already planning it (a bit unclear from your post), I highly suggest going to the NUE christmas market as well. Arguably my favorite (although Rothenburg is a pretty close second). It's about a 5 minute walk from the NUE Hbf.
Walking distance is about a kilometre. Google Maps suggests 12 minutes walking time through the pedestrianized zone. With the amount of people in the area at Christkindlesmarkt time (even after the horrible attack in Berlin) 15-20 minutes is more likely.