The western wing of the upper fortress was usually deserted during the late morning hours. Its long, drafty corridors were lined with faded wool rugs that muffled the sound of footsteps, and the high, narrow slit windows set into the thick granite masonry let in only thin, pale beams of silver winter sun. Nila walked down the quiet hallway, the unshaped woolen liner balanced over her left arm. She was tracking the scent of cedar and leather, intending to find Iris in the lower tack rooms to get help sewing the heavy insulation into her winter riding cloak.

As she neared the old tapestry, a forgotten storage room at the...