The Bards of Bone Plain — Patricia A. McKillip

Scholar Phelan Cle is researching Bone Plain-which has been studied for the last 500 years, though no one has been able to locate it as a real place. Archaeologist Jonah Cle, Phelan's father, is also hunting through time, piecing history together from forgotten trinkets. His most eager disciple is Princess Beatrice, the king's youngest daughter. When they unearth a disk marked with ancient runes, Beatrice pursues the secrets of a lost language that she suddenly notices all around her, hidden in plain sight.