My wife insisted on visiting an example of a concentration camp. I was personally worried about the effect of such a dour topic but agreed to go. While it is as sobering as you'd expect it to be, unless you are steeped in World War II history, you will learn some significant things you were most probably not aware of. Our guide, Tatiana, was unbelievably knowledgeable and passionate. She lived in the former East Germany and could add a great deal of dimension based on that. It's a huge space with a number of persevered buildings but you will have to use you imagination to get the full picture since most of the camp facilities were destroyed by the Russians (after they used it themselves). Another vote for having an expert guide to fill in the missing details.
Berlin City Tour portion
This largely bus-based whirlwind tour of Berlin was a decent overview, with a stop for lunch, a view of a segment of the Berlin Wall and the Holocaust Memorial. However, it was not as satisfying as a walking tour would be. It was an add-on to the Sachsenhausen Concentration Camp tour—which took the bulk of our time. If possible, I'd try to get a walking tour also but Berlin's distance from the port means a 1.5 to 2-hour bus ride both ways and there's probably not enough time to do both well.
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