He saw the gas chambers and the incinerators, the mounds of matted hair and the massed shoes of the departed.
After two days touring Auschwitz, the world's most notorious death camp, Amro was absolutely sure of one thing: "It happened. It's reality."
But something else still baffled the 24-year-old Syrian refugee. "I live in Germany. Germans gave me the opportunity to start my life over. They're my friends," said Amro, who asked that his last name not be used because his family is still in Damascus, a city he fled to escape the country's all-consuming war. "I can't understand how people like this could do something like that."
It is a version of the question every German is expected to reckon with, elemental to the country's determination not to repeat the sins of the past.