When Conanaing the Fearless was High King of Ireland he lived at Fenagh for a long time. One day his son Coffa went out to bathe in the lake, but soon got into difficulties, His nurse Rein who was on the shore at the time rushed into the water to help him but both were drowned. Ever since the lake is known as Lough Rein, called after Nurse Rein who gave her life to try to save the King's son. Conanaing then left Fenagh.
Lough Rein lies to the North of the Village of Fenagh.
When the High King lived at Fenagh, a number of his soldiers went to bathe in a small lake nearby. A serpent, that dwelt in the lake devoured them all, and the lake is since called Loch na Peiste. Noboday ever bathed in that lake since. Lough na Peiste lies south of the Village of Fenagh.