Water is the source of all life, and the Slieve Bloom Mountains are the source of two of the great rivers of Ireland, along with countless smaller tributary rivers such as the Camcor, Brosna, Delour, etc.

But the two great rivers which start life in the Slieve Blooms are the Barrow and the Nore, two of the '3 sisters' - the third being the Suir. These rivers flow into the sea in far away Waterford.

The actual source of the Barrow can be traced to a depression on the side of the hill, near the summit of Barna at a height of around 1,500 ft. (500m).It is a very challenging and rewarding hike. Lower down the slopes the river gathers pace and tumbles over the lovely Glenbarrow Falls - a favourite walk with leisure strollers.

The River Nore rises to the west of the Slieve Blooms and flows south of the mountains through Borris-in-Ossory and is joined by the Delour River near Coolrain and by the Mountrath River before turning south to flow through Kilkenny.

The banks of the various rivers provide a wild and varied habitat for many species of Ireland's native flora and fauna, including woodland trees such as hawthorn, oak, birch, holly and maple and a wide selection of birds and animals.