The Reflection on Mount Vitaki
(A Story of The Fey)
By Kristine Kathryn Rusch (2022)

Professor Kyra Row Kirilli feels the pull of the mysterious reflection on the mountain that lies across the Forbidden Valley. Even her husband, with his knowledge of magic, cannot provide an answer. Kyra must embark on a journey to the source herself-a journey no one ever survives.

Set long before the original books (but somehow in a more technologically advanced age) in Fey series,

It’s a trip up a mountain, then down again !