Danube-Auen National Park on both land and water, and other invertebrates, the total number of species in Donau-Auen National Park is estimated to be at least 5,000. Danube-Auen National Park Donau-Auen National Park () covers 93 square kilometres in Vienna and Lower Austria and is one of the largest remaining floodplains of the Danube in Middle Europe. The German word Aue (variant Au) means "river island, wetland, floodplain, riparian woodland", i.e. a cultivated landscape in a riparian zone. The words Aue and Au occur in a large number of German place names—including Donau, the German word for the Danube River—and refer to forests,
Source of the Danube of the Danube." Source of the Danube The Danube is conventionally taken to be formed by the confluence of the two streams Brigach and Breg just east of Donaueschingen. Known as the source of the Danube ("Donauquelle") the source of the "Donaubach" in Donaueschingen itself. Hydrologically, the source of the Danube is the source of the Breg as the larger of the two formative streams, which rises near Furtwangen. There was an active rivalry between the municipalities of Furtwangen and Donaueschingen for the claim of being home to the "official" source of the Danube since the 1950s, sometimes with the