He recalled a "bad feeling" when told to leave his luggage on the train but the horror of the camp was revealed minutes later — even before he heard of the gas chambers.
One man asked the SS if he could take a picture, Shentow told CBC News more than 70 years later.
"They let the dogs loose. And a German Shepherd jumped on that man, straight on his neck. The moaning, the crying, the yelling — heartbreaking. And this was just in front of me," he said. "Blood gushing out of his neck and from his mouth and from his ears. I knew he was dead. 'My god, where am I?'"
Nearby, he said a young woman stepped off the train with a crying baby in her arms.
"The SS walked over to her and pointed, 'Keep it quiet,'" he said. "No matter how hard she was trying to keep the baby quiet, the baby started to cry louder. He ran over to her, grabbed the baby by the legs and threw it against the train. Then I knew, I'm in hell."
Shentow watched those perceived as weak and old get triaged to the left but he was ordered to the right.
"I knew right there and then, I was given another lease on life," he said.
In the years that followed, Shentow doubted he would survive.
"There are no words. It was hell on earth. As a matter of fact when they ask me, 'Was it really that bad?' I say, 'No. It was 100 per cent worse," he said.
Auschwitz was liberated on January 27, 1945. By then, Shentow had been relocated to Dachau concentration camp. He would not be liberated until April 29, 1945 — his 20th birthday.
'I felt guilty to survive'
Shentow was tattooed as prisoner 72585 at Auschwitz — a mark that remains on his arm to this day.
He remembers passing under the camp's gates that read, "Arbeit macht frei" (one translation reads "Work will set you free"). He worked 10-hour days but soon came to realize that labour was not the camp's main goal.
"We had to carry heavy stones. Then I saw other prisoners carrying the same heavy stones back to where I picked them up in the first place. So, I knew it was a death camp — this was not a working camp," he said. "We always had to carry back the dead ones because quite a few died during work."
Once a day, prisoners would be fed a small ration of bread and soup — even during the cold winter months after long days of work, he said.
"That question comes out often: How did I survive? When I was liberated, after three years of hell, I couldn't find the right words. I just don't know how I made it. And even today, 70 years later, and I'm still here. Maybe God is watching over me," he says.
He said 17 of his family members, including his parents, sisters, uncles and aunts, did not survive the camps.
"I felt guilty to survive," he said.
Originally from Antwerp, Belgium, Shentow moved to Canada in 1949.
"I felt it's time to start a new life," he says. Shentow lives in Ottawa.
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