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 flows parallel to the river for approximately through the Vienna metropolitan area. It diverges from the main channel in Langenzersdorf in Lower Austria (northwest of the city), flows through the 21st district, and rejoins it at the Danube-Auen National Park in the 22nd district (in the southeast). The channel is about wide; the island varies between in width. The current course of the New Danube and the site of the Danube Island were previously a broad landscape of meadows set aside as a floodplain in the first effort to manage Danube floods, in 1868–75. The left, northern bank of the New Danube is protected by the Hubertus Dam (Marchfeld Protective Dam), completed in 1875.