Like other fairy creatures, they have been linked to the Tuatha De Danann of Irish mythology.
The leprechauns spend all their time busily making shoes, and store away all their coins in a hidden pot of gold at the end of the rainbow.
If ever captured by a human, the Leprechaun has the magical power to grant three wishes in exchange for their release.
Popular depiction shows the Leprechaun as being no taller than a small child,with a beard and hat, although they may originally have been perceived as the tallest of the mound-dwellers (the Tuatha Dé Danann)
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