The Wisconsin cartographer who mapped Tolkien's fantasy world

I love fantasy in general, and have read a ton of it. other than tolkien, I have never read a novel with that strong a sense of geography in a constructed world - specifically, that there is an entire rich land out there, and not just a graph of interesting places with the focus shifting from one point to another. when the hobbits have to go from the shire to rivendell, or aragorn has to take the paths of the dead to reach his destination in time, tolkien really manages to convey the experience of a difficult journey that takes a significant amount of time even when nothing plot-significant is happening along the way.

On the flip side, given how difficult the journey was from the Shire to the Misty Mountain, it always bugged me that it seemed like Bilbo got home pretty easily.