Lobau
The Lobau is a floodplain in the southeast of Vienna, pressed against the northern bank of the Danube. Napoleon retreated here after his first military defeat and used the terrain as a base to plan his next campaign. Within the two centuries that followed, this same stretch of river became a UNESCO protected wetland and a beloved nudist swimming spot. What does a floodplain have to offer that keeps drawing people back, generation after generation?
On the 21st and the 22nd of May, 1809, the War of the Fifth Coalition brought Napoleon's army to the banks of the Danube. Austrian forces under Archduke Charles waited on the northern side. Napoleon had ordered his troops across near Kaiserebersdorf, but the Danube split into several wide arms here and there were no bridges to use.
Jean Lannes, counted among Napoleon's most trusted marshals and a central figure in his campaigns, died in the fighting. The battle ranged across open fields and through the villages of Aspern and Essling, north of the Lobau.
After the battle, Napoleon withdrew his forces onto the Lobau, which at that time was an island sitting between branches of the Danube. He established his headquarters there and remained for several weeks, regrouping. Then, on the night of the 5th of July, 1809, Henri-Gatien Bertrand had several bridges constructed across the river. By early morning, 150,000 men had crossed to the left bank, and Napoleon launched an immediate assault on the Austrian army. The decisive victory that followed was fought at Wagram.
Paris still carries the Rue de Lobau near the Hôtel de Ville, and the Avenue de Wagram leads to the Arc de Triomphe. On the Lobau itself, Napoleonstraße, a French cemetery, Napoleon's powder magazine, and monuments near the Panozzalacke all mark the ground where he sheltered. The Lion of Aspern and the French crossing site south of Groß-Enzersdorf complete the memorial landscape.
The Danube regulation project of 1870 transformed Vienna's relationship with the river. Development and infill concentrated on the southern bank, where urban expansion pressed hardest. The northern bank, farther from the city, faced less pressure, and the Lobau survived as a space used for hunting, forestry, and agriculture.
Crown Prince Rudolf was a regular visitor to the Lobau when it served as a royal hunting reserve. In 1903, Emperor Franz Joseph I and King Edward VII of Britain arrived for a hunting trip together. Two years later, the area was formally designated a protected area. In 1918, Emperor Charles I gave the Upper Lobau outright to the city of Vienna.
In 1996, the Lobau was drawn into the Danube-Auen National Park, which stretches downstream into Lower Austria. That designation connected the floodplain ecologically to Ramsar-protected wetland areas in Slovakia and the Czech Republic, forming a trilateral cross-border reserve.
The idea of routing a Danube-Oder Canal through the Lobau first surfaced in 1719. Construction finally began in 1939, during the Nazi era, cutting through terrain that had been a protected area for over three decades. Work was eventually halted, leaving 4.2 kilometers of navigable canal in place.
The Lobau Oil Harbor was established alongside the canal, complete with a refinery and large tank storage facilities. The canal divided the Lobau into an Upper section, opened to agriculture, and a Lower section that remained largely wild. Forced laborers, primarily Soviet prisoners and Jews, were used in the construction of the refinery. It became a target of bombing raids during the war.
The Lobau Groundwater Works, constructed during the same period, still provides Vienna with drinking water during peak demand. Small areas of the Lobau were also designated for military exercises. The division of the area into Upper and Lower sections by the canal would shape conservation decisions for decades to come.
Between 1977 and 2016, the Lobau held UNESCO Biosphere Reserve status, recognition of its ecological importance at an international level. Since 1978, it has been a formal nature reserve. In 1983, the Lower Lobau received Ramsar Wetland designation.
The Eurasian beaver had been extirpated from Austria before its reintroduction to the Lobau in the 1970s. It now shares the floodplain with more than 30 mammal species. Among them are wild boar, European otter, roe deer, and several bat species, including the common noctule, Natterer's bat, and Daubenton's bat.
The wetlands and forests shelter a variety of reptiles, including the European pond turtle, the Aesculapian snake, the dice snake, and the grass snake. Amphibians include the European tree frog, the agile frog, the European fire-bellied toad, and the Danube crested newt. Among the birds, the white-tailed eagle and the common kingfisher both rely on the floodplain's waterways.
On dry gravel terraces known as Heißländen, a savanna-like habitat develops on deep deposits where water is scarce. Hawthorn, sea buckthorn, barberry, and feather grass grow here alongside various orchids, lichens, and mosses. The European mantis, a species native to extremely dry environments, is also found in these areas.
The insect community includes the green snaketail dragonfly, the Eurasian baskettail dragonfly, the southern festoon butterfly, and the stag beetle. Among invertebrates, the noble crayfish represents the region's crustaceans, and the zebra spider shares the area with the tarantula wolf spider.
Deepening the Danube's riverbed, a process intensified by hydropower development, has steadily lowered the water table beneath the Lobau. The formerly flood-prone landscape shifted into one fed primarily by groundwater. Many of the river's old side arms became stagnant pools, slowly filling with sediment.
The Lower Lobau is now experiencing rapid desiccation. The receding groundwater table shows in the frequent drying of surface waters. During particularly dry years, the retreating water exposes extensive mudflats. Specialized plants have colonized those flats, including spikerush, mudwort, beggarticks, and club-rush, each adapted to temporarily bare shorelines.
The oxbow lakes and ponds in the area dry out completely in some years. Sediment deposits, shifts in the Danube's flow patterns, and inadequate water management have compounded the deterioration. As water levels fall, the biodiversity of the floodplain is diminishing.
The 135-meter Josefsteg pedestrian bridge spans the Schröderwasser through a dense stand of common reed and was rebuilt in 2020. It crosses a landscape where the terms of the floodplain's survival are still being worked out.
After World War I, the Lobau opened itself to ordinary Viennese life. Tram line 317 from Kagran carried people to the floodplain's edge for hikes and lazy days beside the water. Crowds, by most accounts, were absent.
In the 1920s, naturism took hold in the Lobau, whether officially permitted or not. Along the old river arms, naturist groups established meeting spots that survive to the present day. The Lobau became one of the rare places near a major European capital where nudist outdoor culture put down permanent roots.
The Dechantlacke and Panozzalacke are among the most popular swimming spots in the Lobau. A nature trail called Obere Lobau runs from the park entrance at Saltenstraße to the entrance at Dechantweg. The floodplain also connects to the European long-distance trails E4 and E8 and the Ostösterreichischer Grenzlandweg. The landscape protection zone extends to Aspern and covers a quarter of Donaustadt. In legal terms, the wild edge of Vienna is considerably larger than any single trail map suggests.
Common questions
What battle was fought at the Lobau in 1809?
The Battle of Aspern was fought on the 21st and the 22nd of May, 1809, during the War of the Fifth Coalition. It was Napoleon Bonaparte's first military defeat and resulted in the death of Marshal Jean Lannes. Napoleon withdrew to the Lobau after the battle and later used it as the staging point for the Battle of Wagram.
When was the Lobau designated a nature reserve?
The Lobau was designated a protected area in 1905 and became a formal nature reserve in 1978. The Lower Lobau received Ramsar Wetland designation in 1983, and in 1996 the Lobau was incorporated into the Danube-Auen National Park. It held UNESCO Biosphere Reserve status from 1977 to 2016.
What wildlife lives in Vienna's Lobau floodplain?
The Lobau supports more than 30 mammal species, including the Eurasian beaver, which was reintroduced in the 1970s after being extirpated from Austria. Reptiles include the European pond turtle and the Aesculapian snake, while birds such as the white-tailed eagle and common kingfisher rely on its waterways. Endangered invertebrates include the green snaketail dragonfly and the southern festoon butterfly.
What happened at the Lobau during World War II?
Construction of the Danube-Oder Canal through the Lobau began in 1939, and the Lobau Oil Harbor was established with a refinery and tank storage facilities. Forced laborers, primarily Soviet prisoners and Jews, worked on the refinery, which was later targeted in bombing raids. Work on the canal was halted after 4.2 kilometers had been completed.
Who gave the Upper Lobau to the city of Vienna?
Emperor Charles I of Austria gave the Upper Lobau to the city of Vienna in 1918, ending its status as an imperial holding. The area had previously served as a royal hunting reserve, visited by Crown Prince Rudolf and, in 1903, by Emperor Franz Joseph I together with King Edward VII of Britain.
What long-distance hiking trails pass through the Lobau in Vienna?
The Lobau is connected to the European long-distance trails E4 and E8 as well as the Ostösterreichischer Grenzlandweg. A dedicated nature trail called Obere Lobau runs from the park entrance at Saltenstraße to the entrance at Dechantweg. The landscape protection zone around the Lobau extends to Aspern and covers a quarter of Donaustadt.
All sources
9 references cited across the entry
- 3Wildbadeplatz Panozzalacke2023-05-24
- 4Lobau: Wasser und AuWiedenegger Elisabeth — 2024-06-14