Visited Auschwitz in 2005, there was a ceremony happening and a man was standing there in his old tattered camp garb. Tattoo on his arm was visible, very old and obviously a survivor.
I don't know what they were commemorating but think it had something to do with the date the first people arrived.
Everyone should go there, it literally burns into your brain just how horrible people can be. I shake my head at those that deny history.