Of name Caer-Merdin called, they took their way:
There the wise Merlin whylome wont (they say)
To make his wonne, low underneath the ground
In a deep delve, far from the view of day,
That of no living wight he mote be found,
Whenso he counselled with his sprights encompassed round.
“And if thou ever happen that same way
To travel, go to see that dreadful place;
It is a hideous hollow cave (they say)
Under a rock that lies a little space