Quoting wholesale from here, to where I got from M John Harrison's blog here.
Matthew Cheney's work has been published by English Journal, One Story, Web Conjunctions, Strange Horizons, Failbetter.com, Ideomancer, Pindeldyboz, Rain Taxi, Locus, The Internet Review of Science Fiction and SF Site, among other places, and he is the former series editor for Best American Fantasy. He teaches English and Women's Studies at Plymouth State University. Read his blog, the Mumpsimus
Maps in books are often more fascinating to me than the books themselves, because maps suggest possibilities. When I first learned to read, I tried hard to get through Treasure Island, but it defeated my skills and bored me. I didn't care, though, because there was that gloriously undetailed map. That's all I'd really wanted from the book, because with the map, I could make up whatever stories or characters I wanted.
The first book review I ever wrote was for a fanzine when I was in my mid-teens. It was a review of L.E. Modesitt'sThe Magic of Recluce, a book I adored, and the review was all gush, but I felt obligated to include some sort of complaint for fear that nobody would take me seriously, and I realized I did have a complaint: No maps! Later, Tor started putting maps in some of the Recluce books, so apparently I wasn't the only one who wanted them.
What did I want from maps in those books? Pragmatically, a sense of relative distances, but that's not really necessary to a reading of a book -- no, what I wanted and want from fantasy maps was another way of abstracting the world. The words, of course, are one level away from the imagined reality, one approximation of it, and a map is another shot at that.
There's no need to pretend maps are accurate. Peter Turchi's marvelous bookMaps of the Imagination: The Writer as Cartographer shows that even the simplest maps are vastly more complex than we might take them to be on first glance. Maps, like stories, are products of convention and imagination. Looking at maps as stories and stories as maps is one way to break through the clutter of everyday chaos.
Barry Lopez's short story "The Mappist" is one of the most magical stories I've ever encountered (you can find it in his book Light Action in the Caribbean). It doesn't contain a map, but you'll learn more about maps and fantasy and life from that story than most. It belongs on the shelf with Borges's great cartographic tale, "Of Exactitude in Science", wherein the greatest cartographers in an Empire finally create a map so detailed and perfect that it is the same scale as the Empire itself, and so proves useless to later generations.
Finally, I would be remiss if I didn't mention a less celebratory view of maps, that of Anne McClintock in her extraordinary book Imperial Leather: Race, Gender, and Sexuality in the Colonial Contest, where the map in H. Rider Haggard's King Solomon's Mines is given a close reading, one in which the map reveals the racial and gender assumptions of the characters and their world. It's a tour de force of interpretation. Maps were very useful to the story of colonialism, because no map is neutral, and therefore to some extent all maps are propaganda, as the Berlin Conference of 1884 and 1885 so well proved, accelerating the Scramble for Africa in pursuit of territories the Europeans gave themselves. Talk about fantasy -- there, fantasies of power and wealth conspired to impose a map on reality.
Perhaps we should say of all maps: Here there be dragons.