Here’s something I’ll betcha didn’t know: there really was–and still is, sort of–a place called Narnia. It was, for almost 3,000 years, a town in Italy; and in 1870, its name was changed to “Narni” (http://www.narniainitaly.com/). It’s still there, perched up in the mountains.
We can be pretty sure C.S. Lewis knew all about it: he would have read Livy’s History of Rome. Because of its strong, defensible location, and not its size or wealth, Narnia was for a long time kind of an important place.
There is no record of fauns or talking animals having lived there, but I would rather not commit myself as to centaurs.
Now go out there and win a trivia contest.