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.
Danube Park
In 1895 it was decided that a park will be formed instead of a bog. The muddy and sandy watery depression was covered with earth, leaving a small body of water which was bricked and turned into a lake. A small island remained in the lake. It was named "Eržebet", after the Empress Elisabeth of Austria, empress consort of Austria-Hungary. When she was assassinated in 1898, a weeping willow was planted in her honor on the island. The lake was formed on an altitude of . The lake and the island are today simply called "Jezero" and "Ostrvce", meaning "lake" and "islet".