In Brythonic mythology, Cwn Annwn are the hounds of Annwn. A pack of snow-white, red-eared spectral hounds which sometimes took part in the kidnappings and raids the inhabitants of the underworld sometimes make on earth, called the Wild Hunt.
Cwn Annwn have their origin in Welsh tales. The pack is known as the spectral hunt.
In Welsh they are associated to the sounds of migrating wild geese, and are said to be leading the souls of the damned to Hell.
The phantom chase is usually heard or seen in midwinter and is accompanied by a howling wind.
Another name of theirs is Cwn Mamau, standing for hounds of the mothers.
The words Cwn Annwn stand for hounds of the otherworld or underworld.
They are Welsh phantom dogs seen as a death portent. Their growling is louder when they are at a distance, and as they draw near the growling grows softer and softer.
In Welsh stories this land is the ever-living, and is full of magical beasts and treasures.
Almost every area in Britain has its version of phantom or fairy dogs.