Gole del Rio Sass: The Secret Basalt Canyon of Val di Non

The Val di Non is the valley of apple orchards. From the windows of the train running through it, rows of apple trees follow one another in orderly lines along the slopes for kilometers. Beneath this agricultural surface, the valley hides a surprising geology: volcanic basalts, erosion-carved gorges, canyons that seem to belong to another landscape. The Rio Sass is the most spectacular of these phenomena — a stream that has cut through ancient lava flows for centuries, leaving vertical walls of black rock up to 30 meters high.

The canyon and the walking route

The Rio Sass forms a gorge of about 2 kilometers that can be walked on a trail equipped with metal walkways and steps carved into the rock. The route starts from Cles, capital of the Val di Non, and descends toward the valley floor in about 90 minutes one way. The basalt walls create a humid, cool microclimate even on the hottest days: bring a sweater even in July. Access is free and without reservation; the trail is open from April to October.

Kayaking and the water descent

For those who practice kayaking or canoeing, the Rio Sass is one of Trentino's most interesting technical stretches: Grade III and IV rapids under normal conditions, with flows that vary considerably between spring (snowmelt) and summer. Some local guides in Cles organize accompanied descents with equipment rental at about 45 euros per person. The best season is April-May, when the water is high and the canyon is immersed in spring vegetation.

The Val di Non and the castle of Cles

Cles, from which the gorges are accessed, is the capital of the Val di Non: a town of 7,000 inhabitants with a medieval arcaded square and the Palazzo Assessorile, frescoed in the sixteenth century as one of the finest examples of provincial Renaissance painting in Trentino. The castle of Cles, partially open to visitors, overlooks Lake Santa Giustina — an artificial reservoir that covered the old medieval center, whose remains appear during extreme droughts. The Val di Non is reached from Trento in 45 minutes by car along the SS43.