Morva is a section of Prydain which is basically a barren swampy wasteland where very few people make it out alive. It used to be a place where black market trades were made by outlaws and wizards until the Horned King sent his 2 dragons there to tear the place apart for the Black Cauldron, destroying the place, killing everyone, and having no luck finding it at all. The ones who kept it, the Witches of Morva, were able to cleverly hide the Cauldron and ensure that the Horned King was convinced that the Cauldron was never here. Thus, over the next 27 years, the Witches were the only ones who lived in this abandoned place as all the destroyed monuments were dismantled by them and taken to their cove for outside black-market trade. Any intruders that entered this place were mostly turned into frogs by the witches, thinking that they were there to steal something from them, including the Cauldron for the Horned King. Now, Morva is surrounded entirely by swamp lands, with it's only inhabitants being the witches.