Six swimmers will attempt to become the first people to swim around Ireland later this summer when they embark on the journey of around 1,287km (800 miles), starting from Carrickfinn beach in north-west Donegal.
Launching details of the Round Ireland Swim expedition at the weekend, Minister of State for Transport Pat the Cope Gallagher described the event as "one of the most inspiring, unique and challenging marine projects" attempted in European waters.
The swimmers will take part in relays and will swim up to 25 miles a day. Depending on weather conditions, it is expected the swim will take between five and eight weeks. Already, the organisers have raised more than €10,000 for the RNLI crew training fund.
The event has taken over a year to plan, with the organisers having to take into account everything from tides and currents to shipping lanes.
"You have to bear in mind that we will be going through a lot of places where there is a lot of marine activity, like Belfast Lough and Dublin Bay," said expedition leader Henry O'Donnell from Donegal.
"Safety is paramount and we will have a fully-trained support team and command vessel with us the whole time."
Derek Flanagan, the marine co-ordinator, added: "While we have charted out our route, so much is dependent on the weather so we must try and plan each day to get the maximum advantage from tides and currents."
The members of the swimming team are Henry O'Donnell; brother and sister Ryan and Anne Marie Ward (Donegal); Ian Claxton (Dublin); Tom Watters (Galway) and Nuala Moore (Kerry).
The swim gets under way on July 2nd from the blue flag beach at Carrickfinn and the swim will go clockwise around the Irish coast.