The Passer (German pronunciation: [pasɐ]; Italian: Passirio [pasˈsiːrjo]) is a 42.6-kilometre (26.5 mi) torrent in northern Italy, a left tributary of the Adige, whose entire course lies within South Tyrol . The stream rises near the Alpine pass between Italy and Austria known as the Timmelsjoch , and flows through the Passeier Valley where the most important settlement is St. Leonhard in Passeier . The river joins the Adige at Merano , where it is a significant site for competitive canoeing, beneath the Steinerner Steg .