The Bès is a small Jurassic-limestone river in the Alpes-de-Haute-Provence that rises in the Trois-Évêchés massif and runs south to join the Bléone just above Digne. Most people driving through the area are heading somewhere else — Digne itself is a quiet spa town, the main Provence tourist routes are further south. The Bès is therefore that rare thing: a perfectly good French wild-trout river that hardly anyone bothers to fish. It is textbook limestone water — clear, cold, aquifer-buffered, the flow steady all summer when the schist rivers of the Cévennes are in August retreat. The fish are modest in size but confident and well-fed; the limestone geology produces reliable caddis and Baetis hatches through the whole season. Stalking water more than anything else. Walk upstream, watch the pool tails, and wait for a fish to show. The best beats are in the middle Bès above the Clues de Barles, where the river runs through a narrow limestone valley that holds the water cool even in July.

• Limestone