Source of the Danube
As early as 1847 the following definition can already be found in the "Universallexikon des Großherzogtums Baden" (Universal Lexicon of the Grand Duchy of Baden): “Danube, the biggest river of Germany, rises at the Martinskapelle in a wild and lonely area of the Black Forest, is called Brege at its origin and forms the river Danube in Donaueschingen where it is unified with the Brigach." (German original: „Donau, der größte Fluß Deutschlands, entspringt bei der Martinskapelle in einer wilden und einsamen Gegend des Schwarzwaldes, heißt am Anfang Brege… und bildet erst in Donaueschingen, wo sie sich mit der Brigach vereinigt, die Donau.“)
Danube–Oder Canal
On December 8, 1939 Rudolf Hess inaugurated the then-named "Adolf Hitler Canal", today Gliwice Canal (Polish: "Kanał Gliwicki") from Kędzierzyn-Koźle at the Oder River to the city of Gliwice, that replaced the historic Kłodnica Canal finished in 1812. At the same time, Hess also performed the groundbreaking ceremony for the further "Donau-Oder-Kanal". The work on the Upper Silesian side already discontinued in 1940. Only a few kilometres of the planned 40-km long channel from Vienna to Angern at the Morava River were actually dug in the years up to 1943, mainly in the areas around the Lobau floodplain in the Donaustadt district of Vienna and the adjacent town of Groß-Enzersdorf. The branch-off at the Danube, just under 100 meters long, is still clearly recognizable today, connecting the "Ölhafen Lobau" of the OMV oil company. Two further sections are today used for swimming and fishing.