In Welsh mythology and folklore, Cŵn Annwn (, "hounds of Annwn") were the spectral hounds of Annwn, the otherworld of Welsh myth. They were associated with a form of the Wild Hunt, presided over by Gwyn ap Nudd (rather than Arawn, king of Annwn in the First Branch of the Mabinogi).
In Wales, they were associated with migrating geese, supposedly because their honking in the night is reminiscent of barking dogs.
Hunting grounds for the Cŵn Annwn are said to include the mountain of Cadair Idris, where it is believed "the howling of these huge dogs foretold death to anyone who heard them".
According to Welsh folklore, their growling is loudest when they are at a distance, and as they draw nearer, it grows softer and softer. Their coming is generally seen as a death portent.
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