[2] While there is no shortage of mythological water-dwelling female beings in European culture, the Gwragedd Annwn are distinct in that, despite the circumstances of their origins, they do not have the characteristics of any sea creature.
This makes Gwragedd Annwn unique compared to other beings of myth such as Selkies (Scottish "sea-maidens") or Merrows (Irish mermaids).
The Gwragedd Annwn can only be found near lakes and rivers, and are not said to live in the ocean, another factor which sets them apart from other aquatic fairy or mermaid-like creatures.
At some point, myth holds that a farmer caught one of these pure white cows, and it provided him with butter, milk, and cheese of the highest quality.
In some variations of the legends, the milk from this mystical cow could heal injuries, make a person more intelligent, and put anyone in a cheerful mood.