Shale bedrock underlies this river. Atlantic salmon are assessed by the Environment Agency against each river's Conservation Limit — many principal rivers are classed 'at risk' with mandatory catch-and-release byelaws; check current rules before fishing. Tarka country — Henry Williamson's Torridge rises on the Bude Formation sandstones of north-west Devon near Welcombe, loops through Sheepwash and Dolton, past Halsdon and Beam, before joining the Taw in the joint Taw–Torridge estuary between Instow and Appledore. The lower main river runs onto Culm Measures shale — flashy, impermeable catchment that colours quickly after rain and clears equally quickly. The upper Torridge around Sheepwash and the tributaries — the Okement (which drains off Dartmoor granite) and the Lew — are first-rate wild brown trout water with strong upwinged and sedge hatches from April through autumn, sparsely fished and full of character. The famous sea trout and salmon beats sit on the lower river: Beam, the historic Halsdon water (now a Devon Wildlife Trust nature reserve), and the legendary Half Moon Hotel water at Sheepwash — Charles Inniss's territory and the local sea trout institution. Night sea trout fishing from mid-June is the headline modern sport.

• Shale