You could spend a year here and not see everything; best to follow the colour coded signage to the time periods you want to focus on; and the I.M. Pei addition is worth a stroll.
Very nice place to learn about German history and definitely worth to visit. Reasonably priced (8 EUR per adult),free for youth below 18-years old.Additionally free entrance on German Unification Day.
History geeks will love this museum. Covers German history from Charlemagne till German-reunification and the different aspects of life throughout. Only downside is organization is a bit confusing.
Monumental collection of German history. Beautiful building. Not everything is bilingual, but there's enough English to guide oneself thru if you don't get the audio guide. Cafeteria Kuechen are so-so