It's the end of our visit to Auschwitz-Birkenau and, as the group gathers in silence by the site of the demolished gas chambers and crematoriums, we look back at the camp, at the train tracks and the gate which leads us out.

There's a profound irony felt by everyone as we make the long walk down the track leaving a trail of candles behind us.

We can leave Birkenau and return to our homes and our lives. But for the millions who came more than 60 years ago, there was no way out. The tracks that pave the way home for us marked the end of line for the prisoners at Auschwitz.

Derry pupils, accompanied by MP Mark Durkan came to Auschwitz on Wednesday, the first group from Northern Ireland on a one day trip organised by the Holocaust Education Trust.

This is stuff you won't learn from a history book or by watching Schindler's List. There are no words to describe the horror of Auschwitz-Birkenau.

"There are those who will tell you the Holocaust never happened," says Rabbi Marcus.

"But here we are in this hell hole. It's the silence that I find overwhelming, and I think of the loneliness that people felt when they arrived here."

For the director of the Lessons from Auschwitz project Alex Maws, the trip is based on the principle that often seeing something is better than reading it.

"It's learning about history," he says, "but also reflecting on the contemporary relevance of that history. We hope that those on our trips take lessons from what they see and bring them back to their community."

For SDLP leader Mark Durkan, who was instrumental in ensuring the project was brought to Northern Ireland, it was an intensely emotional trip.

Visibly moved and shaken Mr Durkan said: "It's hard to take in and talk about. What's been good is that the trip hasn't just been about the statistics, it's about the humanity of the people.

Moved to tears

"We can feel a powerful empathy by watching films about Auschwitz but coming here makes it different. "

Pupils and teachers from Oakgrove College, Foyle and Londonderry College, Lumen Christi College, St. Cecilia's College, St. Joseph's Boys, St. Peter's High School, Thornhill College, St. Columb's College and Belmont House School were often moved to tears as they walked around the camp.

Caoimhe Miller from St Cecilia's College said:"A rabbi told us 9/11 would have to happen every day for two years to equal the number of people that actually died in Auschwitz.

"It's very emotional, it happened so many years ago but it still affects people now. People there were really emotional and crying. You can't really learn just by textbooks, you have to actually see it."

The visit to Auschwitz One, the Polish army barracks, which the SS commandeered and turned into a forced labour camp in 1941, is thought provoking one. We're told not to take pictures inside but the horrors that unfold inside the buildings have the young people reaching for their cameras.

The pupils gasp as they enter a room full of hair, and there's tears as they point out one little pink shoe among the piles of black ones.

In the next room hairbrushes, pots and pans, shoe polish - all stolen from the Jews.

The guide at Auschwitz tells us how the Nazis often lied to those who came to the camp.

There's a picture of three small children smiling and holding hands as they're led to the gas chamber. Nazis deceived Jewish prisoners until the last moment of their lives, we're told. After selection those taken to the gas chamber were told they were going for showers and even allocated pegs so they could find their clothes afterwards. Then the doors were shut.

In Auschwitz One, the gas chamber is still intact, as is the crematorium.

We're asked to be silent as we walk in, to respect the thousands that died there. And the reality of the place is too much for some. It's cold, damp and suffocating, you can see the scratch marks on the doors. Lighted candles mark the spots where so many people lost their lives.
Next door is the crematorium, a reality that's too hard to face.

Cell 18 is where Saint Maximlian Kolbe was held and a place where many go for reflection.

In July 1941 a man from Kolbe's barracks in Auschwitz vanished, prompting SS-Hauptsturmführer Karl Fritzsch to pick 10 men from the same barracks to be starved to death in Block 13 (notorious for torture), in order to deter further escape attempts. One of the selected men, Franciszek Gajowniczek, cried out, lamenting his family, and Kolbe volunteered to take his place. He was canonized in 1982.

'Life changing experience'

Next to Kolbe's cell you can see where prisoners have carved their names on the walls, visitors touch the carvings hoping to touch a piece of history. Among the death and evil, there's also a thought for those who fought to survive.

"It's the human element that was so explicit," says St. Cecilia's teacher Susan Parlour. "For the girls, this trip was a life changing experience. They've learned the history at school but only really felt the big impact when they saw it first hand. They're shocked that such an atrocity could have occured while the world watched."

A short coach ride away is Auschwitz II - Birkenau, the purpose built death camp and main extermination centre.

Prisoners were housed in buildings originally erected as stables, herded together in freezing cold bunks with no blankets or mattresses. The sanitation barrack reveals further horror. Lines of latrines where people were not even given the dignity of privacy when using the toilet. No soap, no towels, not even toilet paper.

We're told how prisoners could only shower every few weeks and ate very little, many of them dying with dysentery.

But it's the railway track that the pupils focus in on. And the suddenly the questions start flowing.

Alex Maws says this is because people are often most affected, not by what they see, but what they don't see.

The tracks and buildings remain in Auschwitz, but the human beings who arrived in the trains are gone and that's what we want to remember.

The group walks to the site of crematorium, notoriously blown up on the orders of Himmler in 1945. Again the questions come, how long after the trains arrived were people put to death? Did they see the smoke and know where they going? How were the selections made?

No one knows how many people died at Auschwitz, but it's though to be 1.2 million.

We leave Auschwitz thankful we're going home, but we'll never forget it.