Echoes of the Otherworld - The Celtic Otherworld is a strange, supernatural dimension where the usual laws of time and space do not apply. The Otherworld encompasses the land of the dead, the realm of the gods, the fabled western isles, the kingdom under the sea and the fairy mounds. Humans venture into it at their peril, but those who realize their innate virtues on the quest returned endowed with supernatural powers, special knowledge or magic gifts.
Juliette Wood. The Celtic Book of Living and Dying.