I always wanted to visit Dusseldorf and this year I got to see it during the Christmas market season.
There is a major construction project going on, in the center of the city, so moving about is not very easy, especially with the thousands of people out, shopping. Do not attempt driving there, park in an underground parking and walk. It will save you a lot of trouble. If you are willing to not pay attention to those details, the Christmas market will definitely impress you.
It stretches over six different central locations. The street food is what impressed me the most. They have a huge selection of foods.
We tried venison soup, wild boar stew with spätzle and fruit chutney, we found my favorite little Dutch pancakes called poffertjes. Of course the gluhwine is present everywhere and noticed that this year the cups are pretty large and more expensive than in past years. But...when in Rome... Go and eat your way through the Christmas market.