When we look for sources of information about fairies we often, logically, turn to folklore and anecdotal accounts. And so we should as these are good, solid sources of information. But we do have another sources about the Irish Good Folk, and arguably an equally important source: mythology. In Irish culture these beings aren't limited to later folklore but appear throughout written mythology as well, going back to the 5th* century Echtra Condla.
In the earliest account, the aforementioned Echtra Condla, we find a story of a woman of the Otherworld who appears to Connla, son of the king. No one else can see or hear her but they can see Connla's interaction with her. She tells him that she is of the people of the fairy hills and describes the place as "an immortal land where there is no death or the sin of transgressions. We have our harvest feast without labor; peace cloaks us without strife". She then invites Connla to go with her, his father's druid intervenes, blocking her for a time, but eventually Connla does indeed go with the fairy woman, never to be seen on earth again.
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