The riders halt beside a waiting cave,
ragged darkness guarded by an unshaped stone.
The woman slips to the dark man's arms, and she
is robed in green. Her hair, all free, is gold.
The woman waits; the man goes forward. Dark
around him closes as she sings of sleep
flowing north, weaves a spell of stream and brook.
The stone rolls closed to seal away the cave.
From the Naming of the Lost by Valerie Nieman Colander
In the Vulgate Merlin, Broceliande is the place of Merlin's entrapment by Viviane and this is used in later texts as well. Broceliande was a real forest, a place of enchantments according to the Breton popular legend. A remnant of the forest, Westward of Rennes, is today clled Paimpont and still has Arthurian association.
According to the story, Viviane seduced Merlin and learned his powers. She cast a spell on him and locked him sleeping in a cave.
Picture: Gustave Dore. "And the dead, Oar'd by the dumb," Idylls of the King.