The Isar is a tributary of the Danube. The 295 km long river rises in Austria and passes the city of Munich on its way north. The river has a catchment area of approximately 9000 km² and bridges a height difference of 848 metres.
The river rises at an altitude of 1200 metres in the Karwendel Mountains, fifteen kilometres from Scharnitz in Tyrol. It flows through the Hinterautal until Scharnitz. Just past Scharnitz is the former border fortress Porta Claudia, where the Isar enters Germany.
From now on, its course follows a glacial valley and at Mittenwald the Isar is already a serious river. The most important cities on the German route are Bad Tölz, Munich, Freising and Landshut. The mouth in the Danube is at Plattling.
The main tributaries of the Isar are the Loisach (right) and the Amper (left). After the Inn, the Isar is the most important water supplier of the Danube on German territory and the fourth longest river in the state of Bavaria.
The Isar has been used to generate electricity since the beginning of the 20th century. Furthermore, the river is largely canalized, also to reduce the risk of flooding: the Isar discharges a lot of meltwater from the Alps in the spring. In Munich, the canalization, which had already begun in 1806, was reversed over a length of eight kilometers between 2000 and 2011. The river is not navigable except for rowing boats, kayaks and the like.
Wikipedia.