The Joe Barr 500 gets underway tomorrow.
This is a non-stop 500-mile (800KMs) World Ultra-Cycling Association accredited endurance cycling race.
Participants will cycle around Donegal’s wild Atlantic coastline in the first 300-mile section before the road carries them inland into the Sperrin Mountains of County Tyrone.
There are various categories with individual and team events. Among the competitors is Donegal's Jason Black.