The
Amper (known in its upper reaches as the
Ammer) is a river in southern
Bavaria, Germany – the largest tributary of the
Isar river. The Amper flows in a generally north-eastwards direction, reaching the Isar in
Moosburg, from its source in the
Ammergau Alps, with a flow of 45 m³/s. It runs through the
Ammersee; upstream of the Ammersee it is known as the Ammer. Its major tributaries are the Glonn (located near
Augsburg), the Würm (the outflow of Lake Starnberg), and the Maisach.