A Limestone lake of 22,000 acres connected by an underground channel with Lough Corrib, holding large brown trout, large ferox trout, also famous for record pike, silver eels and perch. Mayfly are best from mid-May to mid-June on Lough Mask; daddy-long legs and grasshoppers are most common from late July and august. Fishing methods wet fly, dry fly, dapping & spinning. Clonbur, Ballinrobe and Cong are good centres. River fishing on Finney and canal joining Mask and Corrib.