The Aurino comes down off the Rieserferner group below the Birnlücke pass, deep in what's now a protected nature park, and runs about fifty kilometres through the Tauferer Ahrntal before it gives itself up to the Rienza near Bruneck. It's granite country up here rather than the limestone further south in Trentino, and the water carries that clarity — cold, hard, faintly grey-green over the boulders. The valley has a real reputation among Italian fly anglers for holding all three of South Tyrol's headline species in one system: wild brown trout through the pocket water, marble trout in the deeper holding pools lower down, and grayling scattered through the gravel runs between. Fishing rights along most of the river are privately managed, which keeps the pressure sensible and the water in decent shape. It isn't a secret river exactly, but it's a quiet one — long valley, small villages, and water that rewards someone willing to walk a bit further than the car park.

• Granite schist