Lough Derg 4.75

Lough Derg, historically Lough Dergart, is a freshwater lake in the Shannon River Basin, Ireland. It is the second-biggest lake in Ireland and the third-biggest on the island of Ireland .It is a long, narrow lake, with shores in counties Clare, Galway, and Tipperary . It is the southernmost of three large lakes on the River Shannon; the others being Lough Ree and Lough Allen. Towns and villages on Lough Derg include Portumna, Killaloe & Ballina, Dromineer, Terryglass, Mountshannon and Garrykennedy.The lake's name evolved from the Irish Loch Deirgdheirc. This was one of the names of The Dagda, an Irish god, and literally means "red eye".GeographyAt its deepest, the lake is 36 metres deep and covers an area of 130 km² (50.2 sq miles). Close downstream from where Lough Derg empties into the Shannon are the falls of Doonass, the largest fall on the otherwise gently sloping river. Nearby is the location of the hydroelectric power plant at Ardnacrusha, which, when built in 1927 was the world's largest.