The lower slopes of the Blackmount and Rannoch Moor drain into Loch Tulla and the outflow of this 4km long loch is the River Orchy.
The Orchy flows South for its first 4km across bare and boggy moorland until it is joined by its main tributary the Kinglass.
It then heads Southwest through the scenic Glen Orchy where it tumbles down though a series of spectacular falls, gorges, rapids and glides for a further 12km.
It then levels off and passes for about 11km through flatter land with lovely natural gravelly pools before finally reaching its destination, the freshwater Loch Awe.
Loch Awe is Scotland's longest loch and its outflow is controlled by a hydro electric dam which feed the River Awe.
The River Awe is just 6km long and meets the sea in Loch Etive just North of Oban.
an angler fishing Upper Craig Beat
All the Orchy's salmon pass through a fish lift in the barrage at the head of the river Awe where there is a fish counter.
With Loch Tulla at its head, the Orchy is not a true spate river but its flow and fishing conditions are very dependent on the rainfall which, thankfully, is plentiful in this part of the West Highlands.
To accommodate the wide variety of conditions that anglers might face, all methods are permitted except the use of prawn and shrimp.
Strict conservation rules are applied to ensure that a healthy spawning population is maintained.
As soon as fish pass the Awe barrage in April, they will run the Orchy and can be caught right up to the middle beats.
The main Summer run of fish starts in mid June and is tailing off by August but the river is full of fish by September as it is the main spawning ground for the system.
The gravel beds of the lower river attract most of the grilse with the bigger fish mainly being found above the falls on the central beats.
Both daily and weekly lets are normally available throughout the season.
Fishing is mainly concentrated from May onwards with some beats fully booked from September but day tickets normally available on others right up to the end of the season on October 31st.