Preparing to visit Auschwitz-Birkenau

Going to travel there later this week, and I must ask myself...
How does one prepare to go into the depths of a place of such evil?
To seek to witness to attempt to grasp
The enormity of the suffering deprivation inhumanity?

http://en.auschwitz.org/lekcja/1/  A little lesson introducing the place, the people, the mass exterminations

The books of Robert Wistrich are very instructive such as HItler and the Holocaust 
http://www.amazon.co.uk/dp/1842124862/ref=rdr_ext_tmb

Also, have found study of the book by Facing History and Ourselves entitled Holocaust and Human Behaviour to be helpful as well. 

An excerpt from Chapter 7 of the above book:

Over the years, Auschwitz has become a symbol of the Holocaust. It represents the 
thousands of camps through which millions of Europeans died. Israel Gutman, the 
Director of the Center for Holocaust Research at Yad Vashem in Israel, estimates that 
about 85 to 90 percent of all those murdered at Auschwitz were Jews. Among the others 
were Russian prisoners of war and “Gypsies.” Most were selected for immediate death. 
The rest were kept alive for slave labor. Surviving one selection was no guarantee that  one would survive the next. Nothing in one’s previous existence prepared an individual for Auschwitz. Primo Levi, a Holocaust survivor, wrote that soon after arriving there, “we became aware that our language lacks words to express this offence, the demolition of a man. In a moment, with almost prophetic intuition, the reality was revealed to us: we had reached the bottom. It is not possible to sink lower than this; no human condition is more miserable than this, nor could it conceivably be so.”

Neither our vocabulary nor our standards for behavior can adequately imagine this 
history. In reading or hearing the accounts of survivors, Professor Lawrence Langer 
notes, “one is plunged into a world of moral turmoil that may silence judgment...but 
cannot completely paralyze action, if one still wishes to remain alive... As one wavers between the ‘dreadful’ and the ‘impossible,’ one begins to glimpse a deeper level of reality in the death camps, where moral choice as we know it was superfluous and inmates were left with the futile task of redefining decency in an atmosphere that could not support it.”

 Facing that history is extraordinarily difficult, but it is necessary for one 
simple reason: The Holocaust happened. That in itself is a fact that we can neither erase nor evade. Many students use their journals to reflect on what they read and view. As one student wrote, “This history is grim and it can build up inside and make you feel ugly and hopeless. At times I did. My journal was a confidant that no person could have been because it was always there.