Into the Wild by Jon Krakaeur ?

Question

What could be a visual symbol for the book?

Answer 1

Are you talking about symbols in the book? The car that he loved so much but ended up abandoning to start his journey.

or wilderness.

Answer 2

A single visual symbol could be hard, but I think depicting huge trees, large open space, big blue sky, and one small man just standing there, sort of in awe of it all, intimidated but excited, alone, represents Chris's view of the wild, and really the world in general, as portrayed by the book.