A mountain endurance runner from County Leitrim is hoping to run up and down Croagh Patrick an incredible 15 times today, breaking two world records in the process.
Ricki Wynne, a roofer from Drumshanbo, is hoping to break the world record for the greatest vertical distance covered by foot in 24 hours (uphill and downhill).
The current world record is just over 22,676 metres.
If Ricki beats that, he will also break the record for the most times up and down Croagh Patrick in 24 hours.
Ricki is one of Ireland's best endurance runners, with victories at the Seven Sisters Skyline event in Co Donegal, the Portumna Ultra, where he holds the course record, and the Gaelforce Mountain Run.
Ricki is raising money for the Irish Motor Neurone Disease Association.
The 'Ricki versus The Reek' challenge got under way at 10am this morning.