Location: Danube River, Lower Austria Map
Area: 93 km²
Danube-Auen National Park (Nationalpark Donau-Auen) protects
one of Central Europe’s last large, near-natural floodplain
landscapes along the free-flowing Danube east of Vienna,
stretching toward the Morava confluence and the Slovak border.
The park covers roughly 9,300–9,600 hectares. About 65 percent
is riparian forest, 15 percent meadows, and 20 percent water
(main channel, side arms, oxbows, sloughs, and ponds). Seasonal
water-level swings of several meters continually reset habitats
through erosion, sedimentation, and flooding. That dynamism is
why the park holds such high species richness: around 800–900
vascular plants, 39 mammal species, about 100 breeding bird
species (far more if migrants and winter visitors are included),
8 reptiles, 13 amphibians, 60–67 fish species, and thousands of
invertebrates. Total species richness is estimated at 5,000 or
more.
The park is a mosaic of softwood and hardwood alluvial
forest, flood meadows, gravel banks, reedbeds, dry “Heißländen”
(gravel steppe patches), the Marchfeld protective dyke, and
north-facing slope forest on the Vienna Basin escarpment. Each
zone has its own characteristic plants and animals.
What the park actually is
The motto is “Free River. Wild Forest.”
Since 1996 the park has been restoring side arms, reconnecting oxbows,
and letting the Danube rebuild gravel banks and driftwood piles instead
of locking everything behind dikes.
Wildlife worth watching for:
European beaver (gnawed trees are common)
White-tailed eagle
Kingfisher
European pond turtle
Danube fish such as pike, bream,
and sterlet
Spring and autumn migratory birds
Best viewing is from
water or from a quiet trail at dawn, not from a crowded picnic meadow.
Best time to visit
April–June: Fresh leaves, birds, and
wildflowers. Trails can be muddy after floods.
July–August: Hottest
and most humid. Good for swimming and boat trips, worst for mosquitoes.
Pack repellent.
September–October: Color in the floodplain forest,
fewer people, still workable weather.
November–March: Visitor centers
close or drop to winter hours. Trails stay open but paths flood, days
are short, and ranger programs shrink.
Always check Danube water
levels before you go. High water closes trails and side-arm boating.
Official gauge: Lower Austria water-level service (Pegel / Durchfluss).
Two visitor “doors”
Treat the park as two halves.
1.
schlossORTH National Park Centre
Schlossplatz 1, 2304 Orth an der
Donau
Tel. +43 2212 3555
schlossorth@donauauen.at
This is the
main hub for Lower Austria: exhibitions, shop, booking desk,
Schlossinsel wetland garden, walk-in underwater viewing tank, and ranger
tours.
2026 hours:
20 or 21 March to 1 November: daily 9:00–17:00
(some listings still show 18:00 in high summer; confirm on the official
site the week you travel)
2 November to 20 March: winter closure;
phone bookings Mon–Fri 9:00–13:00
Info desk and shop are free.
Exhibitions, museumORTH, and Schlossinsel are ticketed. Recent combined
castle/park tickets: adults about €15, children/youth €10, family €30.
Dogs are not allowed in the centre or on Schlossinsel. Parts of the
building and Schlossinsel are wheelchair accessible.
2. National
Park House wien-lobAU
Dechantweg 8, 1220 Vienna
Tel. +43 1
4000-49495
This is the Vienna-side door into the Lobau. Multimedia
exhibition, garden, playground, picnic tables, and starting point for
Lobau walks. Typical season: early March to early November,
Wednesday–Sunday 10:00–18:00. Building entry is free; guided tours are
extra. Dogs are not allowed in the building or garden.
A third info
point sits at Schloss Eckartsau.
The landscape itself has no entrance
fee. You pay only for indoor exhibitions and guided programs.
How
to get there from Vienna
Public transport works well.
North
bank / Orth / schlossORTH
VOR buses 550, 552, or 553 from U2
Aspernstrasse toward Groß-Enzersdorf, Schönau, Orth an der Donau,
Eckartsau, and Stopfenreuth. Get off at Schloss Orth.
South bank
S7 toward Wolfsthal from Wien Floridsdorf, Praterstern, or Wien Mitte.
Stops: Maria Ellend, Haslau, Regelsbrunn, Petronell, Hainburg. From
Haslau a passenger ferry (no cars) crosses to Orth.
Vienna Lobau
Bus 92B from U2 Donaustadtbrücke (Steinspornbrücke stop, short walk) or
bus 93A from U1 Kagran / U2 Donaustadtbrücke (Naufahrtbrücke).
Car
Lobau: A22/A23, exit Lobau, then Raffineriestrasse.
North
bank: B3 to Orth. Parking near the school / Am Rosenhügel for buses.
South bank: A4 exit Fischamend, then B9.
Driving time from central
Vienna is roughly 20–40 minutes depending on the gate.
The
EuroVelo 6 / Danube Cycle Path runs along the park. Cycling is allowed
only on green-marked cycle routes, not on every footpath, and not after
dark.
What to do
Walk first. There are about 100 km of marked
trails. Stay on them. Off-trail walking is not allowed.
Useful
starter routes:
Orth Circular Trail: about 5 km / 1.5 hours from
the castle area through mixed floodplain habitats. Impassable in high
water. Part of the first stretch is wheelchair-friendly as far as the
Marchfeld dike.
Naturlehrpfad Obere Lobau: easy 6 km nature trail
past Dechantlacke and beaver signs. Start near bus 92B
Raffineriestraße/Biberhaufenweg.
Longer Lobau loops (10–13 km) mix
forest, oxbows, and leftover industrial scars from the oil-harbour area.
Bring your own map. Phone signal is uneven in the forest.
Book a
ranger boat trip. This is the single best way to understand the park.
Rubber dinghy or canoe tours on side arms leave from Orth and other
landings. Rangers explain high-water marks, turtles, eagles, and why
some channels were reopened. Typical length is 2–3 hours. Book at
schlossORTH. Minimum group sizes often apply; Sunday morning family
boats run in season. Children from about age 6 are usually accepted on
standard tours.
Independent paddling is allowed only on designated
side arms in Lower Austria (Schönauer Arm, Kleine Binn, Grosse Binn,
Stopfenreuther Arm, Spittelauer Arm, Johler Arm) and on the main Danube
waterway. No motors on side arms. No docking or stepping ashore except
at marked spots. SUPs are banned. Lifejackets are essential. Small boats
must yield to commercial shipping. Side-arm boating is closed in low
water (nature protection) and in flood (safety). Pleasure boats may not
use the Danube above 600 cm at Pegel Wildungsmauer.
Swim only
where allowed.
Vienna / Upper Lobau: Dechantlacke, Panozzalacke,
Danube-Oder Canal basins II and III, Stadler Furt.
Lower Austria:
Schönauer Au plus designated Danube banks, especially the Orth islands
and Stopfenreuth Auterrasse.
Swimming is banned in other Lower
Austrian backwaters. Scuba diving is forbidden.
Schlossinsel at Orth
is the easy indoor-outdoor introduction: pond turtles, snakes, and a dry
underwater viewing window with Danube fish. Good with children before a
longer walk.
Schloss Eckartsau is a Habsburg hunting palace on the
north bank and a useful second information stop if you are cycling the
Marchfeld side.
Rules that actually matter
These are enforced,
not suggestions.
Stay on marked paths. Cyclists stay on green cycle
paths only.
Dogs on leash at all times. No dogs in visitor-centre
buildings or Schlossinsel.
No camping or tents anywhere in the park.
Nearest campsite is in Petronell-Carnuntum.
No fires. Extinguish
cigarettes fully and take the butts out.
No drones.
No horseback
riding.
Leave at dusk. Night recreation is discouraged so nocturnal
animals can move.
Take all rubbish out. There are almost no bins in
the field.
Do not pick protected plants. Tiny personal amounts of
common berries or mushrooms from the path edge are tolerated; commercial
collecting is banned.
Closed gravel banks and “stop” signs protect
nesting little ringed plovers. Do not walk there.
No commercial
filming or organized events without a permit.
Flood and storm
risk is real. Fallen trees are left in place. Do not walk closed paths.
Check weather and water before you start.
Practical packing list
Waterproof shoes or boots. After rain the Au is mud.
Mosquito
repellent from late spring through summer.
Binoculars.
Printed
trail map plus offline map.
Water and snacks. Food options inside the
forest are scarce.
Lifejacket if you paddle.
Light rain jacket
even in summer. Thunderstorms build fast over the Marchfeld.
There
are no mountain rescue huts. A charged phone helps, but do not rely on
coverage in every oxbow.
How long to stay
Half day: wien-lobAU
plus Obere Lobau trail, or schlossORTH plus Orth circular walk.
Full
day: castle + ranger boat + riverbank swim or a 10+ km loop.
Two
days: north bank (Orth, Eckartsau, Stopfenreuth) one day, south bank /
Hainburg / Carnuntum Roman site the next.
This is a day-trip park
from Vienna, not a multi-day wilderness trek. Overnight in Vienna, Orth,
Hainburg, or Petronell. Do not plan to sleep in the floodplain.
Pair it with nearby stops
Carnuntum archaeological park and Petronell
Hainburg old town and Braunsberg viewpoint
Danube Cycle Path toward
Bratislava
Vienna’s Donauinsel if you want a more urban river day
instead
Official site and current maps: donauauen.at. Download
the English recreational map (Freizeitkarte) before you leave. It marks
swimming zones, boatable arms, and landing kilometres on the main river.
An untamed river before the engineers
Until the 19th century the
Danube east of Vienna was a braided, shifting river. It split into arms,
built gravel islands, cut new channels, and flooded widely. That
constant change created the mosaic that still defines the park: riparian
forest, side arms, oxbows, wet meadows, and dry sandy “Heißländen.”
Settlement and intensive farming stayed limited because summer floods
and winter ice made the lowlands dangerous. Large parts of what is now
the park remained imperial hunting ground rather than farmland. Crown
Prince Rudolf, writing in 1888, called the floodplain near Vienna “an
absolutely unique and isolated piece of wilderness found in the
immediate proximity to a world capital.”
The Lobau, the Vienna
section of the floodplain, had already passed through many owners. In
the early 11th century Emperor Henry II granted the then-island
landscape to the Bavarian monastery of Weihenstephan. Habsburg hunting
rights later covered much of the area. In 1745 Maria Theresa assigned
revenues from Herrschaft Kaiserebersdorf, which included the Lobau, to a
welfare fund for poor Viennese, but the court kept the hunt. Napoleon
used the floodplain as a military landscape during the 1809 Battle of
Aspern-Essling. Through all of this the river itself remained the main
architect of the land.
Regulation: the river is forced into a new
bed
The great change came with the Vienna Danube regulation of
1870-1875. Engineers cut a new main channel, built the Hubertusdamm and
other levees, and created the Alte Donau as a cut-off oxbow. Side arms
were separated from regular flow. Groundwater dropped. Sediment settled
in stagnant channels. Vegetation shifted from a highly dynamic wetland
toward more static forest. Navigation and flood control improved. The
ecological cost was the loss of the river’s ability to rebuild itself
across most of its Austrian course.
From the 1950s onward a nearly
continuous chain of hydropower plants completed the transformation of
the Austrian Danube. After that work, only two longer free-flowing
stretches remained in the country: the Wachau upstream of Vienna, and
the reach east of Vienna that would become the national park. Forestry
also intensified in the alluvial woods. The landscape that survived was
already a fragment, but it was still one of the largest remaining
floodplain complexes in Central Europe.
Early protection, war,
and industry
Conservation began earlier than the national park. The
Viennese Lobau was declared a nature preserve as early as 1905. After
World War I, Emperor Charles I transferred large parts of the Upper
Lobau to the City of Vienna, and “Red Vienna” opened former court
hunting land to the public. Wartime need had already left marks: fields
were plowed in the floodplain during World War I food shortages.
The
Nazi period cut deeper. From 1938 to 1945 much of the later park was
labeled a “Hunting and Nature Preserve of the German Reich,” yet that
title did not stop construction of an oil harbor, a refinery, a
pipeline, and work on the unfinished Danube-Oder Canal. Prisoners of war
and forced laborers worked in the wetlands. After 1945 those industrial
scars remained, especially in parts of the Lobau.
Modern conservation
planning restarted in the 1970s. From 1973 there were first concepts for
a Danube-March-Thaya Wetlands National Park. In 1977 the Lower Lobau
received UNESCO biosphere reserve status (later lapsed). In 1978 the
Lobau became a nature protection zone. In 1982 Lower Austria designated
the Danube-March-Thaya wetlands as a landscape protection area. In 1983
both the Danube-March-Thaya wetlands and the Lower Lobau were listed as
Ramsar wetlands of international importance. Those labels were real, but
they were not strong enough to stop a dam.
Hainburg, 1984: the
occupation that saved the floodplain
In 1984 the planned Hainburg
run-of-river power plant threatened the last long free-flowing Danube
reach east of Vienna and the riparian forests around Stopfenreuth and
Hainburg. Permits were already in hand. Clearing began. Conservation
groups, including WWF Austria under the slogan “Rettet die Auen,” called
for resistance. Thousands of people occupied the Hainburger Au. The
action became known as the Hainburger Aubesetzung, or Hainburg Movement.
It drew students, scientists, families, and public figures and is still
treated as a turning point in Austrian environmental politics and in the
rise of the Green Party.
Police attempts to clear the forest in
December 1984 failed to end the occupation. The federal government
declared a pause for reflection. In January 1985 the Supreme Court
banned further deforestation. In March 1985 the Konrad Lorenz
Volksbegehren collected 353,906 signatures demanding a ban on large
plants such as Hainburg and the creation of a national park. On 1 July
1986 the Administrative Court cancelled the plant’s water rights.
Scientific surveys that followed found more fish species than planners
had assumed and concluded that the floodplains east of Vienna were
worthy of national park status - and that a dam was incompatible with
that status.
From protest to a state treaty
The park still
took more than a decade. In 1989-90 WWF’s “Natur freikaufen” (“Ransom
the Environment”) campaign secured 411 hectares of the Regelsbrunner Au,
a purchase later backed by a large public fundraising broadcast. In 1990
the Republic of Austria signed a preparatory agreement with Vienna and
Lower Austria. From 1991 to 1995 the Marchfeldkanal operating company
carried out detailed national park planning.
On 27 October 1996, in
the courtyard of Hainburg Castle, Environment Minister Martin
Bartenstein, Vienna Mayor Michael Häupl, and Lower Austria Governor
Erwin Pröll signed a treaty under Article 15a of the federal
constitution. That act founded Donau-Auen National Park. The
Nationalpark Donau-Auen GmbH began work on 2 January 1997. In 1997 the
IUCN recognized the park as a Category II protected area. The founding
agreement explicitly kept the Danube as an international waterway and
protected groundwater used for drinking water. Initial size was about
9,300 hectares, with a long-term aim of bringing in further floodplain
tracts. The park was later expanded, including an addition of 277
hectares in 2016.
After 1996: letting the river work again
Since designation, commercial forestry has stopped over large areas.
Deadwood, structural diversity, and old-growth features have increased.
Meadows and dry grassland sites are still managed where needed. The
white-tailed eagle returned as a breeder. The park now holds Austria’s
last reproducing native population of the European pond turtle and
characteristic floodplain plants such as black poplar, water soldier,
and wild grape.
The most important modern work has been river
restoration with viadonau and EU LIFE projects. Cut-off side arms at
Haslau-Regelsbrunn, Orth, Schönau, and later the Hainburger Johler Arm
and Spittelauer Arm were reconnected. Near Hainburg almost 3 km of hard
bank protection was removed so the Danube could rebuild its own shore
for the first time in about a century. Similar work followed at
Witzelsdorf. The long-term engineering idea is to remove a large share
of the remaining hard bank works between Vienna and the border, restore
floodplain connection, and slow riverbed incision while still serving
navigation.
The park also became an organizer of international river
conservation. DANUBEPARKS, launched on its initiative, links protected
areas from Bavaria to the Danube Delta. Cross-border work with Slovakia
on tributaries such as the Fischa and Schwechat has treated the
Vienna-Bratislava reach as one ecological corridor. Visitor
infrastructure grew around Schloss Orth, the Schlossinsel, and the
Nationalparkhaus Wien-LobAU. About two million people now use the area
each year for walking, cycling, canoeing, and ranger-led programs. The
working motto is simple: “Freier Fluss. Wilder Wald” - free river, wild
forest.
Habitats that structure life
Softwood riparian forest (Weiche Au)
sits closest to the river and side arms and floods several times a year.
Pioneer trees and shrubs recover quickly after high water. Hardwood
riparian forest (Harte Au) occupies slightly higher ground that floods
less often but is still tied to groundwater pulses. White poplar often
forms the transition. Oak, ash, maple, lime, and elm dominate older
stands. Deadwood is left in place and supports beetles, fungi, and
cavity-nesting birds.
Flood meadows and regularly mown or grazed
openings hold species that need both moisture and light. Gravel islands
and banks are pioneer surfaces. Heißländen are dry, heat-retaining
gravel mounds with steppe-like vegetation, lichens, and mosses. The
19th-century Marchfeld dyke is an artificial dry habitat that now
supports over 400 plant species, including many orchids. Slope forest on
the south bank includes Austria’s lowest-elevation beech stands, which
mark the flood line because beech cannot tolerate inundation. Pools at
the foot of the slope are important amphibian breeding sites.
Flora
Vascular plant diversity is high because wet, moist, and dry
microsites sit side by side. Softwood forest is built around black
poplar (Populus nigra), white poplar (Populus alba), crack willow (Salix
fragilis), purple willow (Salix purpurea), white willow, and alder.
Black poplar is now scarce across much of Europe and is a conservation
priority here. Hardwood forest adds field elm (Ulmus minor), oak, ash,
maple, and lime. Shrubs include dogwood (Cornus sanguinea), blackthorn
(Prunus spinosa), hawthorn, buckthorn, and Cornelian cherry (Cornus mas)
on drier rises.
Climbing plants are conspicuous: hop (Humulus
lupulus), traveller’s joy (Clematis vitalba), and the rare wild
grapevine (Vitis vinifera subsp. sylvestris), which is extremely
endangered in the Austrian Danube floodplain.
Spring geophytes carpet
the forest floor: Alpine squill (Scilla bifolia), snowdrop, lesser
celandine (Ficaria verna), lily-of-the-valley (Convallaria majalis),
ramsons, and broad-leaved Solomon’s seal. Autumn brings meadow saffron /
autumn crocus (Colchicum autumnale) on wet meadows.
Aquatic and marsh
plants include common reed (Phragmites australis), branched bur-reed
(Sparganium erectum), amphibious bistort (Persicaria amphibia),
arrowhead (Sagittaria sagittifolia), common frogbit (Hydrocharis
morsus-ranae), rigid hornwort (Ceratophyllum demersum), spiked
water-milfoil (Myriophyllum spicatum), pondweeds, bladderwort
(Utricularia vulgaris), and a relict population of water soldier
(Stratiotes aloides). Recent mapping of oxbows recorded 86 aquatic and
marsh species; hornwort, milfoil, and pondweed were among the most
frequent.
Dry and semi-dry sites (Heißländen and the dyke) support
feather grass, cypress spurge (Euphorbia cyparissias), and a notable
orchid assemblage: early spider-orchid (Ophrys sphegodes), bee orchid
(Ophrys apifera), burnt orchid (Neotinea ustulata), military orchid
(Orchis militaris), green-winged orchid (Anacamptis morio), and helmet
orchid. Siberian iris grows in flood meadows. Stinging nettle can form
tall, dense stands in nutrient-rich understorey.
Fauna
Mammals. Red deer reach large size here because of rich forage and
relatively low disturbance in core zones. Roe deer, wild boar, red fox,
badger, pine and stone martens, polecat, stoat, weasel, hedgehog, brown
hare, and red squirrel are widespread. Eurasian beaver (Castor fiber) is
a keystone engineer: it fells trees, creates ponds and channels, and
increases habitat heterogeneity. European otter uses the water network.
European ground squirrel (souslik) occurs on drier open ground. About 39
mammal species are recorded.
Birds. The park is one of Austria’s
strongest wetland bird sites. White-tailed eagle (Haliaeetus albicilla)
is a flagship species; kingfisher (Alcedo atthis) has one of Austria’s
best breeding concentrations. Black stork nests in old floodplain trees.
Other notable species include black kite, little ringed plover, common
sandpiper, corncrake (Crex crex) in tall wet meadows, grey heron, purple
heron, various ducks and rails, black woodpecker, middle spotted
woodpecker, eagle owl, bee-eater in suitable open sandy areas, and many
warblers and reed specialists. More than 100 species breed; total
recorded bird species (including passage and winter visitors) exceeds
300.
Reptiles and amphibians. Eight reptiles include European pond
turtle (Emys orbicularis), dice snake (Natrix tessellata), grass snake
(Natrix natrix), and Aesculapian snake (Zamenis longissimus) on warmer
slope-forest edges. Thirteen amphibians include Danube crested newt
(Triturus dobrogicus), fire-bellied toad (Bombina bombina), agile frog
(Rana dalmatina), edible frog, and European tree frog (Hyla arborea).
Temporary pools and oxbows are critical for breeding.
Fish. The
free-flowing Danube and connected side waters support 60–67 species.
Characteristic or notable taxa include barbel (Barbus barbus), asp
(Aspius aspius), European mudminnow / dogfish (Umbra krameri),
bitterling, pike, zander, wels catfish, chub, and wild-form common carp.
Current-loving species use the main stem; still-water specialists use
oxbows and sloughs.
Invertebrates. Insects and other invertebrates
dominate species counts. Highlights include great capricorn beetle
(Cerambyx cerdo) in old oaks, green club-tailed dragonfly (Ophiogomphus
cecilia), emperor dragonfly, banded demoiselle, European mantis on dry
sites, numerous other dragonflies, butterflies, beetles associated with
deadwood, freshwater mussels (Unio, Anodonta), pond snails, and
freshwater sponges. The combination of flowing water, still water, wet
woodland, and dry gravel produces exceptional invertebrate diversity.
Ecological role and conservation context
The park functions as a
green corridor between Vienna and Bratislava, a flood-retention area, a
drinking-water resource, and a climatic buffer. Many listed species
persist because floods still rearrange the landscape and because
forestry has been stopped in core zones. Remaining threats include
historic river regulation (which isolated side arms), invasive species,
and climate-driven changes in flood timing. Renaturation projects have
reconnected selected side channels and removed sections of bank armour
so the river can again shape its floodplain. Beaver activity now does
much of the “management” that humans used to do by cutting.