I went to Dachau. It wasn't exactly what I was expecting - it just wasn't that horrifying, that is, until I went to the cremation sheds.
Among the upsetting things about the whole camp was the obvious amount of technical prowess that went into building something like this. This combined with that fact that Dachau is really not that far from Munich makes it seems rather obvious that the whole country knew what was up.
Work makes free.