The first-ever Great Dublin Swim is taking place in the city this morning.
Swimmers can swim 750 metres or 1.5km in any stroke for their chosen charity.
The swim is open to all swimmers over 12 years of age and for the competitive swimmers all waves will be time-chipped to find Ireland's fastest swimmers.
The event starts near Sean O'Casey Bridge and finishes up near the Jeannie Johnson.
The event is staggered into different "waves" or groups, with the Elite swimmers beginning at 12 noon.