The Shannon is the largest river in Ireland, and is 386km long from its source at the Shannon Pot in the foothills of the Cuilcagh Mountains in County Cavan to its estuary below Limerick City. It has great stocks of a wide variety of fish including salmon, brown trout, bream, tench, rudd, roach, hybrids, eels, pike and perch.

The best known locations are at Longshore, Corbally, Plassey and The Cut. The spring salmon fishing peaks in late March and April and an average of 500 fish are accounted for each season. The average weight of these fish is 10lbs. During the heavy runs of fish these areas are popular locations and overcrowding occurs. It produces approximately 600 grilse annually.

The popular fishing methods are fly, worm, prawn and spinning and the banks, for most of this stretch, are clear and easily accessible.