unicorndeburgh reviewed The steerswoman's road by Rosemary Kirstein
Review of "The steerswoman's road" on 'Goodreads'
I picked this up based on Jo Walton's recommendation: www.tor.com/blogs/2008/10/not-only-science-fiction-but-more-science-fictional-than-anything-else-rosemary-kirsteins-steerswoman-books
And, wow, was Jo ever right! (I know. Such a surprise.) When you start reading it, the protagonist is at an inn, with other travelers. It looks like the standard medievalish fantasy setting -- there's even a reference to a wizard -- but you couldn't be more wrong. This is science fiction, and the working out of the science is deliciously revealed in the course of a suspenseful story. I loved the characters, and the world, and the mystery. This paperback edition includes the first 2 novels in the 4-book series.
The first book in this series was published in 1989. The rights to all of them have reverted to Kirstein, and she's now publishing them as ebooks, and they're inexpensive.