Hills? In Greenville, NC? 
I almost burst out laughing at that! My husband and I lived there for 3 years in the 1980s, and I remember it well. Flat as the proverbial pancake. There's not much in the way of hills in NC at all, once you get out of the Appalachians, and Greenville is in the coastal plain, which is the flattest part of all.
Also, Asheville to the coast is over 6 hours each way, at today's interstate highway speeds. I can't even imagine how much longer it took in the 1950s. How odd.
I got curious enough to look up where Delia Owens (author of the book) is from, and Wikipedia says she was born and raised in southern Georgia. She spent a little time in Asheville, but I have a feeling she may not have ever gotten any farther east, which may help explain her "fanciful" depiction of North Carolina geography.
This almost makes me want to read the book, just to see what else she got wrong about the Tarheel State! 
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