Hello and welcome to Newsar with Paul Henley in London and me, Tim Franks, in southern Poland.

I'm at Auschwitz, the concentration camp, which became a slave labour camp,

which became perhaps the most notorious death factory in human history.

Today is the 80th anniversary of the liberation

of Auschwitz by Soviet troops. The Nazis murdered almost a million Jews on this site. Jews

weren't the only victims here, but they were the overwhelming number in the Nazi campaign

to wipe out an entire people.

During that all-consuming fire, the Holocaust, 6 million Jews were killed, 40% of the global population.

The enormity of the crime can defy comprehension, and the legacy of Auschwitz, our understanding

of anti-Semitism, of genocide, of how we can allow the most terrible crime still to happen, that remains fiercely contested.

Perhaps for that reason, at the ceremony attended by dignitaries from around the world, it'll be the voices of survivors, those now in their 80s and 90s who somehow made it out alive.

It'll be their voices which predominate, maybe for the last time.

You'll hear one of their stories, an interview I've done, with an astonishing 95-year-old in a few minutes.

First, I'm going to take you inside this campus of horror.

Okay. take you inside this campus of horror. Auschwitz spread to several locations, but this was the original camp.

My guide today is Miroslav Obstarchik who's been guiding people

for more than 20 years I think, is that right?

35 years. Gosh. Where are we going?

So we're going to enter block number four

first part of the exhibition.

Okay. to enter block number four, first part of the exhibition. This is one of the most shocking exhibits you can see here. It's a display case, I guess, probably about 20 metres long, and inside it's barely illuminated by the bleak winter light but there is, well I've just been told two tons of human hair. This was women's hair that was shorn.

It was used by the Germans

...