Art Museum in Wolfsburg.
The Bauhaus Archiv or Bauhaus Archive / Museum of Design in Berlin is certainly the world's premiere institute conserving work from the historic school of the Bauhaus (1919-1933), the most important school of architecture, design, and art of the 20th century.
Just a great colorful weekly market.
http://www.diebergstrasse.de/index.php?id=112&L=2
http://www.expatica.com/de/entertainment/ent_leisure/when-in-heidelberg-head-for-the-hills-31368.html