In the First Branch of the Mabinogi, it is implied that Annwn is a land within Dyfed, while the context of the Arthurian poem Preiddeu Annwfn suggests an island location.

Preiddeu Annwfn, an early medieval poem found in the Book of Taliesin describes a voyage led by King Arthur to the numerous otherworldy kingdoms within Annwn, either to rescue the prisoner Gweir, or to retrieve the cauldron of the Head of Annwn.

* Preiddeu Annwfn, in which Arthur sails to Annwn ( the Otherworld ) to retrieve a magic cauldron ( possibly a predecessor to the Grail )

* XXX " Preiddu Annwfn " (" The Spoils of Annwn ")

The book also includes important poems which were probably not composed by Taliesin, including the Armes Prydein ( The Great Prophecy of Britain ) and Preiddeu Annwfn, ( The Spoils of Annwn ), and the Book of Aneirin has preserved an early Welsh nursery rhyme, Pais Dinogad ( Dinogad's Petticoat ).

Some Welsh and Breton tales and poems relating the story of Arthur date from earlier than this work ; in these works, Arthur appears either as a great warrior defending Britain from human and supernatural enemies or as a magical figure of folklore, sometimes associated with the Welsh Otherworld, Annwn.

The third and final strand is that the early Welsh Arthur had a close connection with the Welsh Otherworld, Annwn.

A large tradition seems to have once surrounded the Battle of the Trees, a mythological conflict fought between the sons of Dôn and the forces of Annwn, the Welsh Otherworld.

The pronunciation of Modern Welsh Annwn is.

Over time, the role of king of Annwn was transferred to Gwyn ap Nudd, a hunter and psychopomp, who may have been the Welsh personification of winter.

Gwyn ap Nudd (, sometimes found with the antiquated spelling Gwynn ap Nudd ) is a Welsh mythological figure, the king of the Tylwyth Teg or " fair folk " and ruler of the Welsh Otherworld, Annwn.

In Welsh mythology, Arawn was the king of the otherworld realm of Annwn, appearing prominently in the first branch, and alluded to in the fourth.

In later tradition, the role of king of Annwn was largely attributed to the Welsh psychopomp, Gwyn ap Nudd.

In Welsh folklore, the Cŵn Annwn or " Hounds of Annwn " ride through the skies in autumn, winter, and early spring.

Pwyll Pen Annwn is a prominent figure in Welsh mythology and literature, the lord of Dyfed, husband of Rhiannon and father of the hero Pryderi.

Hafgan is one of the kings of the otherworld, Annwn, in Welsh mythology.

In Welsh mythology and folklore, Cŵn Annwn (, " hounds of Annwn ") were the spectral hounds of Annwn, the otherworld of Welsh myth.

However, the Annwn of medieval Welsh tradition is an otherworldly paradise and not a hell or abode of dead souls.

* Andrjei Sapkowski's books from the Geralt de Rivia cicle features a form of Wild Hunt heavily based on the Welsh myth on the Cwn Annwn.

According to Culhwch and Olwen, Gwyn was " placed over the brood of devils in Annwn, lest they should destroy the present race ".

The baying of the hounds was identified with the crying of wild geese as they migrate and the quarry of the hounds as wandering spirits, being chased to Annwn.

Later the myth was Christianised to describe the " capturing of human souls and the chasing of damned souls to Annwn ", and Annwn was equated with the " Hell " of Christian tradition.

One influential retelling of this was the fantasy work of Evangeline Walton: The Island of the Mighty, The Children of Llyr, The Song of Rhiannon, and Prince of Annwn.

They include " Kadeir Teyrnon " (" The Chair of the Prince "), which refers to " Arthur the Blessed ", " Preiddeu Annwn " (" The Spoils of Annwn "), which recounts an expedition of Arthur to the Otherworld, and " Marwnat vthyr pen " (" The Elegy of Uther Pen "), which refers to Arthur's valour and is suggestive of a father-son relationship for Arthur and Uther that pre-dates Geoffrey of Monmouth.

Culhwch rode to King Arthur's court with two " Otherworld " dogs accompanying him, possibly Cŵn Annwn.

The Cŵn Annwn also came to be regarded as the escorts of souls on their journey to the Otherworld.

In this poem the owner of the cauldron is not an Irish lord but the king of Annwn, the Welsh Otherworld, suggesting that the version of the story in Culhwch is a later attempt to euhemerize an older tale.

A large tradition seems to have once surrounded the Battle of the Trees, a mythological conflict fought between the sons of Dôn and the forces of Annwn, the Welsh Otherworld, and seemingly connected to the Fourth Branch of the Mabinogi.

* Several poems of Taliesin: Kadeir Teyrnon (" The Chair of the Prince "), which refers to " Arthur the Blessed ", Preiddeu Annwn (" The Spoils of the Annwn "), which recounts an expedition of Arthur to the Otherworld, and Marwnat vthyr pen (" The Elegy of Uthyr Pen "), which refers to Arthur's valour and is suggestive of a father-son relationship for Arthur and Uthyr that pre-dates Geoffrey of Monmouth.

* Cŵn Annwn, hunting dogs of the Otherworld

The Cŵn Annwn also came to be regarded as the escorts of souls on their journey to the Otherworld.

Mallt-y-Nos ( Matilda of the Night ), also known as the Night Mallt, is a crone in Welsh mythology who rides with Arawn and the hounds ( Cŵn Annwn ) of the Wild Hunt, chasing sorrowful, lost souls to Annwn.

The Cauldron of Khath Meigol and its powers of resurrection hark back to Welsh mythology's tale of the Cauldron of Annwn, and a number of the deities seem to have Celtic or Welsh roots: Paul is known as Pwyll after his sacrifice, while Macha and Nemain come straight from Irish mythology.

In Welsh mythology, Cadair Idris is also said to be one of the hunting grounds of Gwyn ap Nudd and his Cŵn Annwn.

In Welsh mythology and folklore, Cŵn Annwn (; " hounds of Annwn ") were the spectral hounds of Annwn, the otherworld of Welsh myth.

One possible interpretation, if the reading is accepted, is that he steals a dog, lapwing and roebuck from Arawn, king of Annwn ( the otherworld ), leading to a battle between Arawn and the Children of Dôn.

Some time later, Pryderi receives a number of otherworldly pigs from his father's old ally, Arawn, king of Annwn, which are stolen through trickery by Gwydion, a Venedotian magician and warrior.

According to the Book of Taliesin, he fought alongside Gwydion at the Battle of the Trees, in which he assisted his uncle in enchanting the trees to rise up in battle against Arawn, king of Annwn.

Annwn plays a reasonably prominent role in the Four Branches of the Mabinogi, four interlinked mythological tales dating from the early medieval period.

In the First Branch of the Mabinogi, entitled Pwyll, Prince of Dyfed, the eponymous prince offends Arawn, ruler of Annwn, by baiting his hunting hounds on a stag that Arawn's dogs had brought down.

On his return, Pwyll becomes known by the title Penn Annwn, " Head ( or Ruler ) of Annwn.

The similarly mythological epic poem Cad Goddeu describes a battle between Gwynedd and the forces of Annwn, lead again by Arawn.

The narrator then describes the cauldron of the Chief of Annwn ; it is finished with pearl and will not boil a coward's food.

" Tradition revolves around Gwyn leading his spectral rouds, the Cwn Annwn (" Hounds of Annwn ") on his hunt for mortal souls.

His role as a psychopomp is paralleled in his later tradition as leader of the Wild Hunt, in which he leads a pack of supernatural hounds known as the Cŵn Annwn to harvest human souls.

* Gwyn ap Nudd, a mythical ruler of Annwn.