Mähdigraben

The Mähdigraben, a left tributary of the Lech, which flows into the Lech near Oberndorf. A very clear body of water with lots of aquatic plants.

The Lech is a right tributary of the Danube. The 256 km long river originates in Vorarlberg in the Hochtannberg region at the confluence of the Spullerbach and Formarinbach streams in the Tannläger valley. It flows through Tyrol and southern Bavaria, where it empties into the Danube. Shortly before the Austrian-German border, it joins the Vils river, forms the artificial Lechfall near Füssen, and crosses Swabia and Upper Bavaria on its way. The largest cities on the Lech are Landsberg and Augsburg; in this city, it receives its largest tributary, the Wertach. The river empties into the Danube near Marxheim.Source: Wikipedia