The Fergus rises in the Burren region of County Clare and flows southwards through the village of Corofin and the town of Ennis to join the tidal waters of the Shannon Estuary at Newmarket-on-Fergus.
The River Fergus flows through around seven lakes before it reaches Ennis town and tidal water. It is a sizable angling district and good fishing for brown trout both on the river and some of the lakes in the catchment.
The river flows through limestone country and is therefore enriched by the high calcium content in the water. This calcium encourages healthy growth in the plant and fish life in the many reed-fringed lakes throughout its length.
Within this relatively compact area there is a wide range of angling available including salmon, brown trout, pike, perch, bream, tench, rudd and eels. In recent years some of its lakes and ponds have produced excellent tench fishing.