OSWIECIM, Poland — To visit Auschwitz is to find an unfathomable but strangely familiar place. After so many photographs and movies, books and personal testimonies, it is tempting to think of it as a movie-set death camp, the product of a gruesome cinematic imagination, and not the real thing.

Alas, it is the real thing.

That is why, since its creation in 2009, the foundation that raises money to maintain the site of Auschwitz-Birkenau has had a guiding philosophy: “To preserve authenticity.” The idea is to keep the place intact, exactly as it was when the Nazis retreated before the Soviet Army arrived in January 1945 to liberate the camp, an event that resonates on Holocaust Remembrance Day, on Thursday.

It is a moral stance with specific curatorial challenges. It means restoring the crumbling brick barracks where Jews and some others were interned without rebuilding those barracks, lest they take on the appearance of a historical replica. It means reinforcing the moss-covered pile of rubble that is the gas chamber at Birkenau, the extermination camp a few miles away, a structure that the Nazis blew up in their retreat. It means protecting that rubble from water seeping in from the adjacent ponds where the ashes of the dead were dumped.

And it means deploying conservators to preserve an inventory that includes more than a ton of human hair; 110,000 shoes; 3,800 suitcases; 470 prostheses and orthopedic braces; more than 88 pounds of eyeglasses; hundreds of empty canisters of Zyklon B poison pellets; patented metal piping and showerheads for the gas chambers; hundreds of hairbrushes and toothbrushes; 379 striped uniforms; 246 prayer shawls; more than 12,000 pots and pans carried by Jews who believed that they were simply bound for resettlement; and some 750 feet of SS documents — hygiene records, telegrams, architectural blueprints and other evidence of the bureaucracy of genocide — as well as thousands of memoirs by survivors.

The job can be harrowing and heartbreaking, but it is often performed out of a sense of responsibility.

“We are doing something against the initial idea of the Nazis who built this camp,” said Anna Lopuska, 31, who is overseeing a long-term master plan for the site’s conservation. “They didn’t want it to last. We’re making it last.”

The strategy, she said, is “minimum intervention.” The point is to preserve the objects and buildings, not beautify them. Every year, as more survivors die, the work becomes more important. “Within 20 years, there will be only these objects speaking for this place,” she said.