Lough Boderg is a lake on the River Shannon on the County Roscommon–County Leitrim border.History and legendThe lake's name is Irish for "Lake of the red cow." Lough Boderg is separated from Lough Bofin ("Lake of the white cow") by the Derrycarne Narrows.Túathal Techtmar used Lough Boderg as one of the traditional boundaries of the ancient Kingdom of Meath: "From Loch-Bo-Deirg to Birra, From Sena eastward to the sea."RecreationLough Boderg is a noted fishery for bream, rudd, roach, northern pike, eel and perch.The North Shannon Yacht Club is based on Lough Boderg.