The Documentation Center was really well done. I recommend starting your day there and buying the day pass. Then you can get in to a handful of other museums that day for free. We chose the Documentation Center and Nuremberg Trial Museum/Courtroom. Anyway...I would give yourself about 3 hours to visit this place. Included in your entry fee is an audioguide. We spent about 2 hours in the museum and didn't listen to the entire guide - there is a lot of information. Then we walked around the lake to visit the grounds.
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