This high mineral content stream, with its clear waters, takes its source in the Navarre province in the steeply-sided valleys bordered by the Aritzakun and Urrizate mountains, and then joins the main Nive river at Bidarray.

Its small river basin, with abrupt valley slopes and almost inexistant human activity, makes this, without doubt, the purest and most well preserved of the Nive tributaries. Vulnerable to low waters levels in summer, fishing becomes particularly difficult as the waters are so clear. Approaching the fish is delicate and must be carried out like a Sioux Indian ! Its features lend itself well to live bait fishing or with flies.