Within the city limits, the river bed consists almost entirely of concrete, which was installed between 1895 and 1899 in order to stop the devastating floods, sometimes accompanied by
cholera, which the river had regularly caused before that time. At the same time, the
Stadtbahn ("city railway") was built, which makes use of the concrete river bed and is separated from the river by only a wall. It is now part of the
Vienna U-Bahn system. Along the course of the river, the
Naschmarkt and the
Theater an der Wien can be found. Much of the river is covered over in the city, particularly in front of
Schönbrunn Palace, in the
Meidling and Naschmarkt neighbourhoods and around
Karlsplatz near the city centre. The River Gate was built in
Jugendstil between the years 1903 to 1906 and was opened to the general public on 15 November 1906. In April 2013, the City of Vienna approved plans to build three terraces along the river valley. Each terrace (or "zone") will cover a total area of . The first terrace was expected to be completed by 2015.
Cycling and walking beside the Wien For safety reasons, cycling or walking in the concrete bed of the Wien is officially prohibited. A continually controversial topic is whether to build cycle paths and footpaths next to the water. Proponents believe the water flow can be safely regulated, while opponents do not believe this is possible. In 2005, a short segment was opened to the public, near
Hütteldorf railway station. It features an audible and visual alarm system to warn users to leave the path if flooding is imminent. Extensions to this path have been proposed, but continue to receive much opposition. The path is open from March to October. ==Nomenclature==