Since its formation caused by the folding of the Alps and sedimentation of the Pannonian Plain until well into the 19th century, the course of the Danube has been constantly changing - both through natural processes and by human engineering.
The engineering of the Danube started in the 19th century and has been systematically carried out since. The most important measure was the Vienna Danube regulation, a programme of extensive flood-control engineering
The Leopoldsberg Panorama (abover) gives an idea of the extent to which the urban development of Vienna was shaped by the Danube with its numerous arms, islands and sandbanks, as well as regular flooding. Floods of varying intensity - often caused by melting snow, ice floes or heavy rainfall - occurred several times a year, constantly changing the riverbed along the Danube.
Regulatory measures were proposed to provide effective flood protection. At the same time, these measures would keep the river, which had, over time, shifted to the northeast, close to the city.
Although plans were repeatedly drawn up and individual measures taken, the Danube remained unregulated in the Vienna area until 1870. After catastrophic floods in 1830, 1849 and 1850, a Danube Regulatory Commission was set up. Most members preferred to create a new riverbed closer to the city – but the Commission did not reach an agreement.
After another serious flood disaster in 1862, a second commission was appointed. In 1868, the project of creating a man-made new river bed was finally approved. The successful construction of the Suez Canal through the 1860s also contributed to the implementation of this ’radical’ solution.
On 14 May 1870, Emperor Franz Joseph I turned the first sod for the work on the regulation of the Danube near Vienna, a project that would cost almost 25 million guilders (more than 11 million euros). At the same time, five bridges were built: the Kaiser Franz Joseph Bridge (Floridsdorf Bridge), the Kronprinz Rudolf Bridge (Reichsbrücke) and three railway bridges.
The work was done 5 years later and the shipping services restarted when the steamship Ariadne carried the Emperor along the new river bed to Nussdorf.
Elswhere, in Bavaria, from 1805 to 1817, Carl Friedrich von Wiebeking was Royal Director General for Water, Bridge and Road Construction, overseeing the regulation of the rivers in southern Bavaria. In Hungary, István Széchenyi led work on regulating the Danube and the Tisza since 1846.
At the Iron Gates - a gorge along the Danube between Serbia and Romania - the worst obstacles were not removed until 1890. Between then and 1896, around 650,000 cubic meters of rock material were blasted out. For navigation, however, it remained the most dangerous section of the Middle and Lower Danube.