Berlin has museums for everything from sugar to transport and technology.
For art lovers, out in Dahlem, there is an art museum with a room full of Rembrandts and two relatively unknown paintings, one each by Brueghel and Bosch. Also, if by chance, ancient history is your passion, the Pergamon Museum is a must-see. The museum features the Lion Gate from Babylon, and a collection of Greek and Roman coins to rival any other. When it is returned, presumably, it will also reside at the Pergamon Museum. There is one other museum that is a should-see in Berlin.