Mael Dúin was a hero in Celtic mythology who travelled on an epic journey. He was the son of Ailill Edge-of-Battle. His story is attributed to Aed Finn from the Eight century. A Celtic cross Like other Iron Age Europeans, the Celts were a polytheistic people prior to their conversion to (Celtic) Christianity. ...

In the story Mael Dúin travels to revenge his father's death upon marauders from Liex. As Liex is across the sea, Mael Dúin seeks the advice of a druid who tells him how to get there and in what manner. Mael Dúin follows the druid's advice but his foster brother's join him and upsets the number of people on the voyage. Because of this Mael Dúin is blown off course and into a great voyage where he encounters many dangers. These include narrow escapes from beasts, visits to old hermits as well as a visit to Tir na nOg the land of eternal youth. Druid can refer to: a priest of the religion of the ancient Celts, see Druidry. ... In Irish mythology, Mag Mell (plain of joy), also called Tir na nOg (land of young), was the underworld. ...

Mael Dúin's story is a curious mixture of Christian and Pagan belief in that when he finally reaches the Liex marauders he does not kill them, compelled to mercy by the fact that God, in the Christian sense, had saved him on his own journeys.