Impressions set in stone.

The Otherworld (Fabricated Memories: Visions of Irish mythology)

The source of fairy beliefs was that a race of people had once lived in the Celtic nations and British Isles that were driven into hiding by invading humans. They came to be seen as another race, or possibly spirits, and were believed to live in an Otherworld.

The Otherworld in Celtic mythology is the realm of the dead or the stronghold of spirits and beings or right alongside the world of the living, but invisible to most humans or
described as existing underground.

Faerie folk:

They are generally portrayed as humanoid in appearance and as having supernatural abilities, various animals have also been described as fairies. One popular belief was that they were the dead (ghosts), or some subclass of the dead.

Leprechaun

Leprechaun, a type of male faerie, they usually take the form of old men who enjoy partaking in mischief, with a mind for cunning. If anyone keeps an eye fixed upon one, he cannot escape, but the moment the eye is withdrawn he vanishes. The leprechaun originally had a different appearance depending on where in Ireland he was found. Yeats, in his 1888 book entitled Fairy and Folk Tales of the Irish Peasantry describes the leprechaun as ‘dressed in a red coat with seven rows of buttons’

Banshee

A Banshee, in Gaelic means, "fairy woman", is sometimes described as a ghost or as a harbinger of death. She is said to be an old woman with long hair that she combs as she cries. If she throws her comb at the person she appears to and they catch it the live, if not they die.