First as a child prisoner of just 4 years old. He has only fragments of memories from his time here: Staring out at barbed wire, running down concrete stairs, hiding in a corner. And one especially vivid memory that still haunts his dreams, the bloodied face of an elderly man.
Last year, he visited the German Nazi-run concentration camp as a survivor. He came for closure and says he felt an overwhelming sense of relief.
During the 70-year memorial for the liberation of Auschwitz on Tuesday, he visited the camp in search for his identical twin brother, separated shortly after liberation.
"Sometimes I stare at people in the street, and I look for someone who looks like me," he said. "My biggest hope is my brother will be here. Maybe from another country. Or maybe another survivor can tell me something, recognize me or remember us both. Anything."
But as he stands in the snow, next to the barbed wire and the brick buildings, his heart pounds. He turns away to hide his tears.
Two lives, two names
Seventy years ago, Menachem Bodner was known as Elias Gottesman, Auschwitz ID A-7733. Auschwitz records show he had a twin, Jeno Gottesman A-7734.
Both were subjected to the medical experiments of Nazi doctor Josef Mengele. And both survived Auschwitz to be taken into a care home for children after liberation.
But Elias was adopted by a man searching for his own wife and children in the chaos and eventually taken to Israel. He was given the new name of Menachem Bodner.
What happened to Jeno Gottesman is unknown.
For decades, Menachem didn't even know he had a twin. His only memory came to him in the form of dreams of another boy, blond like him, sleeping in bed beside him.
It took nearly 70 years and the help of his genealogist, Ayana KimRon, poring over documents for him to prove his instinct was real.
In one sense, she says, his lack of memory is a blessing:
"I'm really happy for him that he lost his memory." She told CNN, "It's so much easier to establish a normal life. But even then, he had nightmares. Just imagine if he remembered."
But it means she must rely on the memories of other survivors to try and track down his twin.
"It's all about the awareness of friends and neighbors. And courage. If he's there and he knows about the search, he'll need some courage to come forward, and then he'll find he has a wonderful family."
A 21st century tool to solve a 20th century puzzle
Menachem has launched a Facebook Page titled A-7734 in the hope that social media will spread word of his search.
There has been progress: A DNA match found Menachem's first cousins in the United States -- the only relatives from his birth family. They had no idea that Menachem was alive and had assumed that he and his entirely family had perished in Auschwitz. It was an emotional reunion, and his cousins gave him a gift: the only photo of his birth parents.
"They told me so much about my mother," he says, smiling. "The most important thing: Now I know my mother's face. Before I had remembered only her blond hair. Now I can see her."
But he still searches for Jeno. And he comes to Auschwitz in the hope he will remember some clue, another survivor will recognize him. Maybe even his own brother.
He says he has new dream now: He sees himself walking in a forest with his brother, wearing identical clothes -- black trousers -- and a short sleeve blue shirt.
Is it a dream or does he believe it will become a reality?
"Maybe, I don't know." He says.
But standing in the snow, outside the very building he was held as a prisoner as a young boy, Menachem insists he has not given up. "No, not at all." He says, "It only makes me want to search for him even more."
In Auschwitz, the place of his nightmares, Menachem still finds hope to dream.