An Irish schoolboy who decided to go swimming in a lake rather than do his homework inadvertently discovered a 4,000-year-old longboat. 

Cathal McDonagh, 12, went wading in a lake at the back of his garden in Lisacul, County Roscommon, and stumbled across a 17-foot longboat buried in the mud. 

Archaeologists have told his family that the boat may date as far back as 2,000 BC. 

(Courtesty Mick McCormack)

(Courtesty Mick McCormack)

The Irish Independent reports that McDonagh tripped over the vessel as he paddled in the shallow water of the lake and says that an expert team will travel from Dublin later this week to examine the find. 

Donal Lafferty, Brendan Greene,  Cathal McDonagh, with mum Eileen, dad Peter McDonagh, Lisacul, Co. Roscommon (Courtesy of Mick McCormack)

Donal Lafferty, Brendan Greene, Cathal McDonagh, with mum Eileen, dad Peter McDonagh, Lisacul, Co. Roscommon (Courtesy of Mick McCormack)

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The lake is home to at least one crannóg - an artificial island used as dwellings and defense mechanisms in prehistoric Ireland. Crannóg's are the oldest dwellings in prehistoric Ireland. 

There are additionally at least seven ringforts surrounding the town of Lisacul. 

Eileen McDonagh, Cathal's mother, told the Irish Independent that he was supposed to be doing his homework when he made the discovery. 

She said that her son became bored with his schoolwork and went for a walk down to the lake, where he paddled up to his ankles in a pair of wellington boots. 

It was there that he tripped over the long piece of ancient wood and made the fascinating discovery. 

Cathal McDonagh, with mum Eileen, dad Peter McDonagh, Breana McCulloch and Declan Greene, putting the log boat back to where it was first discovered near Lisacul, Co. Roscommon. (Courtesy Mick McCormack)

Cathal McDonagh, with mum Eileen, dad Peter McDonagh, Breana McCulloch and Declan Greene, putting the log boat back to where it was first discovered near Lisacul, Co. Roscommon. (Courtesy Mick McCormack)

Cathal's father Peter and his two elder siblings Aonghus and Róisin were summoned to help him retrieve the vessel from the lake and the family then reported the find to the Underwater Archaeology Unit of the Department of Culture, Heritage and the Gaeltacht. 

Experts said that the vessel could date back to Ireland's Neolithic era but that it also could be from the medieval period. The experts advised the McDonagh family to place the vessel back in the water in order to preserve it. 

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