The Adda (Latin Abdua, or Addua; in Lombard Ada) is a river in North Italy, a tributary of the Po. It rises in the Alps near the border with Switzerland and flows through Lake Como. The Adda joins the Po a few kilometres upstream of Cremona. It is long. The highest point of the drainage basin is the summit of la Spedla (a subpeak of Piz Bernina), at .