Danube
"Danube" is an Old European river name derived from a Proto-Indo-European "*dānu". Other river names from the same root include the Dunaj, Dzvina/Daugava, Don, Donets, Dnieper, Dniestr, Dysna, Tana and Tuoni. In Rigvedic Sanskrit, "dānu" means "fluid, drop", in Avestan, the same word means "river". In the Rigveda, "Dānu" once appears as the mother of Vrtra, "a dragon blocking the course of the rivers." The Finnish word for Danube is Tonava, which is most likely derived from the word for the river in Swedish and German, "Donau". Its Sámi name "Deatnu" means "Great River". It is possible that "dānu" in Scythian as in Avestan was a generic word for "river": "Dnieper" and "Dniestr", from "Danapris" and "Danastius", are presumed to continue Scythian "*dānu apara" "far river" and "*dānu nazdya-" "near river", respectively.
New Danube
The New Danube (German Neue Donau) is a side channel built in 1972–88 on the eastern side of the Danube in Vienna, Austria. It was created to provide flood relief by containing excess water. The Donauinsel (Danube Island), made out of the removed material, separates the new waterway from the main channel of the river. The project was referred to by the United Nations Human Settlements Programme (UN-HABITAT) as "the first truly multipurpose fully sustainable flood protection scheme."