The Isar is a river in Bavaria, Germany. It is a tributary of the Danube and 283 km in length. The name Isar appears to be derived from the Celtic word "Isaria" (meaning "torrential").
The source is located on the German-Austrian border in the Bavarian Alps. From there the river runs northwards, directly through the Bavarian capital Munich and northeastward to Deggendorf, where it finally meets the Danube.
Cities on the river's banks include: Bad Tölz, Wolfratshausen, Munich, Freising, Moosburg, Landshut, Dingolfing, Landau and Plattling.