The Barddas of Iolo Morganwg, Vol. I., ed. by J. Williams Ab Ithel, , at sacred-texts.com
God made all living beings in the circle of Gwynvyd at one breath; but they would be gods, 3 and attempted to traverse the Ceugant. This, however, they could not do, wherefore they fell down to Annwn, which unites with death and the earth, where is the beginning of all living owners of terrestrial bodies.
Question. Where is Annwn?
Answer. In the extreme limits of the circle of Gwynvyd. That is, living beings knew not how to distinguish evil from good, and therefore they fell into evil, and went into Abred, which they traversed until they came back into the circle of Gwynvyd.
Q. What ignorance did they commit?
A. They would venture on the circle of Ceugant, and hence became proud; but they could not traverse it, consequently they fell into the circle of Abred.
263:3p. 262 See Gen. iii. 5.