The Adige starts in the Reschen Pass in the "comune" of Graun im Vinschgau, South Tyrol province, at an altitude of about close to the borders with Austria and Switzerland. First, it flows to the south until the confluence with the Ram river and then turns to the east. At Merano, the Adige is joined by the Passirio river and turns to the southeast; in Bolzano, it is joined by the Isarco, its main tributary. In the confluence with the Tasso river, the Adige flows to the south and, then, from Badia Polesine, it turns to the east and flows into the Adriatic Sea to the south of the mouth of the Brenta river and to the north of the mouth of the Po river.