The Authie runs quietly along the old border between Picardy and the Pas-de-Calais, from Coigneux down through Auxi-le-Château and Dompierre to the Baie d'Authie where it meets the Channel in a wide tidal mouth. It's the Canche's less-famous sister — same geology, same hatches, less pressure, and a surprising number of genuinely large fish in the lower meadows where the valley broadens. Wild brown trout through the upper reaches, grayling in the steadier pools, and a sea trout run that brings decent fish up from the bay in autumn. The mayfly comes off around the third week of May; the evening sedge hatches through June can be almost absurd. Much of the best water is private estate, but the AAPPMA beats around Auxi are good and unfussy. A river that rewards knowing it.
- Chalk