I felt uneasy about visiting Auschwitz – particularly when the first thing I saw there was a shop selling postcards and snacks.

While staying in nearby Krakov, I’d thought long and hard about booking one of the Auschwitz tours advertised on practically every street corner.

The Nazi death camp, where more than a million people died, is now a memorial museum, drawing constant streams of visitors, from coachloads of schoolchildren to Holocaust survivors. While opening concentration camps to the public doesn’t seem quite right, they represent a chapter of history that should never be forgotten.

This week, Bradford will mark Holocaust Memorial Day with a ceremony themed Speak Up, Speak Out.

Having visited Auschwitz, the site of such unimaginable horrors, I feel more strongly than ever that we should continue to speak out against hatred and discrimination.

Walking beneath the chilling Arbeit Macht Frei sign, to the sight of rows of wooden barracks surrounded by electric wire fencing, half of me felt I had no right to be there, while the other half felt it was important to understand what happened, and to pay respect to those who suffered.

Shuffling past a wall peppered with bullet holes, we filed into wooden huts where cramped bunks had once crawled with lice and rats.

Further on came ‘mug-shot’ photographs of prisoners, some of them dead-eyed, others clearly terrified. I could barely look at the images of children huddled together next to cattle-trucks, and I have since been unable to get one little boy’s face out of my head.

At the larger Birkenau site, there was an eerie quiet as we stood on the railway platform, in the shadow of the watch-tower.

I thought of the Auschwitz survivor I once interviewed who, on arrival, was stripped naked, had her head shaved, and was told she no longer had a name, just the number scratched on to her skin. “Within 45 minutes, they de-humanised me,” she said.

Our guide told us of survivors who had returned to the site. One man, who’d arrived as a teenager, recalled his mother pushing him away on the platform. He later realised she was trying to distance him so he wouldn’t be sent with her and his younger siblings to the gas chambers.

Another survivor fell to her knees, pulling up handfuls of soil as she cried over the family she had lost.

When I went home a few days later, I felt like part of the place was clinging to me.

Two years on, I still occasionally wake up from a dark dream of barbed wire and wooden huts, thinking of that bewildered little boy stumbling out of a cattle-truck.