This part sounded dubious to me too, but then I visited the wikipedia page which lists all the killing camps outside Germany (most were in Poland), while some l

This part sounded dubious to me too, but then I visited the wikipedia page which lists all the killing camps outside Germany (most were in Poland), while some labour camps were in Germany proper [1]. [1] https://en.wikipedia.org/wiki/List_of_Nazi_concentration_camps https://en.wikipedia.org/wiki/List_of_Nazi_concentration_cam...