The Castle of the Silver Wheel
First book in a fantasy trilogy by the author of Child of Saturn. Gwelliant of Celydonn possesses the gift of magic. She can hear stones speak, trees talk, and stars sing. As a bride, she accompanies her husband to Mochdreff, where he must act as ruler for a people who are the enemies of Celydonn--where only Gwenlliant's knowledge of magic can bring peace to the land.