I wanted to go to Belzec (pronounced Biwzhets) because no one really does. One million Jews died there in the span of nine months - and hardly anyone knows about it. I felt it was a pilgrimage to a holy site: the second largest (after Treblinka) Jewish graveyard in history. Mike Tregenza was my guide. He is a non-Jewish, English historian who lectures at Lublin university. According to Sir Martin Gilbert, he is the world expert on Belzec. Belzec is a sleepy little hamlet in southeast Poland. A few thousand people live there. All seem to be related in some...