The Elorn runs fifty-six kilometres across the granite of western Finistère and holds the most productive Atlantic salmon population in the Rade de Brest system. It is spate water, and it must be fished as such: wait for the lift, fish the drop. Spring is the best of it — March through May, when the runs concentrate on the rising water after Breton rainfall. Tube flies of an inch and a half in coloured water, reducing to doubles and standard tied flies as the water clears. The best pools lie between Sizun and La Roche-Maurice, on classical Breton holding water: clean gravel in the tails, deeper lies against the bedrock walls of the central pools. Sea trout run with the salmon and take the same flies in daylight, which distinguishes Brittany from the Cumbrian and Welsh waters where the sea trout are strictly a night quarry. Resident brown trout are wild and managed as a patrimonial population. Check the current AAPPMA arrêté before fishing — the salmon season varies year on year and the quota is usually tight.

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