OSWIECIM, Poland - As they do on each anniversary of the liberation of Auschwitz by Soviet troops, witnesses to the Holocaust will gather today, having grown older, frailer and fewer each year.

After 62 years, the camp itself is also showing signs of aging under the pressures of tourism and time.

Its new director is searching for ways to preserve vital evidence of Nazi crimes and update the exhibits without chipping away at Auschwitz's authenticity or giving fodder to Holocaust deniers.

"The biggest dilemma of this place is preserving what is authentic while also keeping it possible for people to see and to touch," said Piotr Cywinski, 34, a historian who took over in September.

"This wasn't built as a medieval castle with strong materials to last for all time," Cywinski said in his office in one of the Auschwitz barracks. "It was a Nazi camp built to last a short time."

Most sensitive, perhaps, is what to do about the remains of gas chambers, which are slowly sinking into the ground from weather, erosion and gravity.

The Nazis blew up the gas chambers and crematoria toward the end of World War II as the Soviet army approached. Today, most are in ruins, as the Nazis left them, evidence of the original crimes and the German attempt to cover them up.

Any decay poses a problem, given the camp's role as evidence of the atrocities inflicted on Jews, Gypsies, Polish political prisoners, homosexuals and others. Still visible are the railroad tracks along which inmates were brought in, the barracks where they lived in inhumane conditions, the gas chambers where they were murdered, and the crematoria where the bodies were burned.

For all that to crumble would deprive future generations of priceless historical evidence of Nazi atrocities, a further concern in light of Holocaust denial. The site provides a clear picture of how the camp operated. Many other Nazi death camps, including Treblinka and Belzec, were dismantled and are marked today only by monuments.

Auschwitz is not one camp, but two, each with its own problems. Auschwitz I was built in an abandoned Polish military base, and Auschwitz II, or Birkenau, is a much larger complex built two miles away during the war to speed up the Nazis' "Final Solution."

At Auschwitz-Birkenau, Cywinski is calling for retaining walls to be built around gas chambers to prevent them from sinking further.

"We are at a moment where we have to act," Cywinski said. "If we don't, there's the risk that in 10 or 15 years, it will no longer be possible to understand their construction."

But "anyone tampering with gas chambers is tampering with the heart and soul of what Auschwitz represents," observes Jonathan Webber, a professor of Jewish studies at the University of Birmingham in England and a member of the International Auschwitz Council, which advises Auschwitz administrators.

Cywinski stressed that all decisions would be made after consulting with authorities on Holocaust commemoration.

One of those is Yad Vashem, the Holocaust memorial in Israel, which says it welcomes the decision to update the museum.

Visit the Auschwitz memorial and museum's

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