A magic forest in ancient Brittany, identified with the forest
of Piampont in modern-day Brittany, which figured in Arthurian
legend. It was in this place that Merlin was enchanted by
Nimue or Viviana, Lady of the Lake, and imprisoned beneath
a huge stone. The name Broceliande is often employed as symbolic
of the dim unreality of legendary scenery.
Lacy, Norris J. The Arthurian Encyclopedia. New York Garland