Somewhere in it, down became up and they began to fall slower and slower instead of faster and faster. Snow, mottled with patches of rock, was skimming below them. Prim put out her hands defensively. The surface came up to meet her. She skidded, then plunged into deep snow that brought her to a stop without breaking anything. When she tried to stand up, she sank to midthigh.

A bright moon was out. A brighter light banked past her, then went back the way they’d come from. Prim watched Mab descend toward a river of chaos that ran through a gorge a short distance beneath them. The sprite hunted back and forth along it for a minute, then plunged back in.

Not far away Prim could hear the uncouth gagging noises that she had come to associate with Corvus’s changing back into his bird form. There was no better place to be a bird. They were very high up in mountains. Half the sky was clear. The other half was stone. Below them chaos filled the lower reaches of a deep straight-sided canyon. Its opposite bank was a sheer cliff topped with a glacier. Beyond that the land dropped away into dark forest.

Her brain put it all together from maps. The cliff on the opposite, or north, side of the canyon was the Precipice. The plateau atop it was the domain where the Shifting Path threaded among hidden crevasses across territory patrolled by Lightning Bears.

They had simply skipped over, or tunneled through, that whole portion of the journey. They would not need to cross the Chasm; they had just put it behind them. They had reached—they were standing on—the Knot. The Fastness must have been nearby.

Four dark forms hurtled up out of the Chasm and tumbled and skidded through the snow around her. Edda took longer to stop than the others, carving a deep gouge in the snow and finally coming to a stop a bow-shot higher up the slope. She was laughing. Her laughter was music, bells, and birdsong. She got to her feet. Looking a little beyond Edda, higher up the slope, Prim perceived that the snow became patchier and soon petered out altogether, giving way to bare rock. Which stood to reason since it was more and more sheltered by the overhanging brow of stone that blotted out half the sky: a place Prim had heard about but never seen depicted on any map, since it could not be. Instead, bards tried analogies: thick ropes knotted together or folds in heavy blankets, except bigger, and made of mountains.