The Vale of Mists was a location on Berengaria VII.
In the year 2155, Richard Stiles observed the Draco Berengarius hunting at night near the Vale of Mists. (ENT - The Romulan War novel: Beneath the Raptor's Wing)
Elias Vaughn was attacked by a Draco Berengarius when he entered the Vale of Mists as a boy. (DS9 novel: The Soul Key)