At the beginning of the book, a traveler says that he had climbed Old Joshua and Sugar Boy "for the memory". Why does Mary Call tell that story? What is its significance?

The scene with the traveler illustrates the contrasts of the land they live on, which can be the most beautiful land seen, or the cruelest. Right now, the Luther family is surviving. However, in the winter, the land will be hard and deadly, and they will still need to survive. The contrast between the beauty and bounty of the land in summer and the harsh nature of winter is a theme throughout the novel and represents the family's struggles through the good time and the bad.