Three family members will cycle from Malin Head to Mizen Head in five days.
Brothers Barry and Damian Fox and their cousin Michael launched the charity bike ride this morning in Newry.
They'll have the support of experienced cyclist Matt Ritchie.
They plan to raise more than the three thousand pounds for local charities PIPS and The Kevin Bell Repatriation Trust.
Speaking to Kevin McAllister on the Q Cafe, Barry Fox said he was inspired after witnessing the Bell family's struggle up close.
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