This one is especially difficult to narrow down because the point of books is to conjure a place (or a time. Or a time and a place) for the reader. And I am blessed with one of the reading styles that can be described as full-immersion reading. It is as close to an out of body experience as I will ever have.
So, there isn't a "best" book for me. There are hundreds of books that have conjured for me a place, real or fantasy, current, past, or future. The three books I've picked are just a few examples of different places that books have taken me. In my mind.