The windowless boxcar is one of more than 700 original objects and 400 photographs from over 20 institutions and museums around the world showing the largest documented mass murder site in human history.

This exhibit comes as Jews are facing greater hostility and danger. Anti-Semitism is up in the United States and around the world, and there were deadly shootings at synagogues in Pittsburgh last year and near San Diego last month. The Anti-Defamation League reports that assaults against American Jews more than doubled from 2017 to 2018.

"At a time of hatred and bigotry we find we need to again be vigilant in every kind of way." Ratner said.

The memory of the Holocaust seems to be fading from people's awareness, according to Ronald Lauder, the president of the Auschwitz-Birkenau Memorial Foundation.

"Three generations later they don't get it," Lauder said. "Let people see the horror of the Auschwitz. The only way to defeat anti-Semitism is through education."

Auschwitz was not a single entity, but a complex of 48 concentration and extermination camps. The exhibit spans three floors of the museum and includes shoes, clothes, striped uniforms with the gold Jewish star that prisoners were forced to wear, luggage and even silverware left behind by the victims.

Luggage, taken from Jewish prisoners, is displayed in the new exhibition at the Museum of Jewish Heritage entitled "Auschwitz. Not long ago. Not far away." on May 2, 2019 in New York. Spencer Platt / Getty Images

A shoe found at Auschwitz, left, and a wheelset from a German freight locomotive are displayed in the "Auschwitz: Not long ago, Not far away" exhibit, at the Museum of Jewish Heritage in New York on May 2, 2019. Richard Drew / AP

Personal grooming items, taken from Jewish prisoners, are displayed in the new exhibition at the Museum of Jewish Heritage entitled "Auschwitz. Not long ago. Not far away." on May 2, 2019 in New York. Spencer Platt / Getty Images

The bunk beds where they slept three and four to a bed. The posts that linked the barbed wire that held them in. The canister that held poison gas.

The SS helmet and dagger of Heinrich Himmler, considered to be the main architect of the Holocaust, are on display as well, along with vintage anti-Semitic propaganda that illustrate the brewing hatred that led to the Holocaust.