It rises in the Mont Preneley bogs at the heart of the granite massif and runs down through the high Morvan woods towards Château-Chinon. The first thirty kilometres are small, cold, and stony — real wild trout country that happens to share its name with a river everyone thinks they already know. Fish it slowly. The Baetis are good from late March onwards, the caddis build from May, and the stoneflies in the rough water are worth imitating through spring. The trout are wild and small-to-medium — six to ten inches is the working average, with the odd surprise in the deeper pool-tails that you did not expect. Upper Morvan water runs cold until May, so the season starts slowly. Nymph in April, shift to dry fly once the first march browns show, and do not expect a river that looks anything like the Yonne of the schoolbook maps. This is a different animal altogether — honest, quiet, and almost entirely unpublicised.

• Granite

• Ecology: High
• Chemical: Failing to achieve good