Tøndermarsken in Southern Jutland

Experience Tøndermarsken's enormous man-made design

Denmark's largest continuous meadow area.

Originally, the Marsh was a marine foreland, which was formed by the deposits of the tides, but through encroachment and drainage, large parts of the fertile nature have today been transformed into a cultural landscape.

What is

Geographically speaking, the Tønder marsh is a large meadow area of approx. 2,500 ha. Most of all, it is reminiscent of a meadow area on which farm animals such as cows and sheep graze daily. But if you look a little closer at the area, you will also be able to see an enormous system of streams, lakes and wetlands, all of which end in Vidåen, which then flows into the Waddensea at Højer.

The drainage of the area transformed the harsh, inaccessible and unproductive landscape into a cultural landscape according to human needs. The development can be seen in the almost geometric division of the area, with ditches and streams as well as remnants of the original swamp and bog landscape in Kogsbøl/Skastmose. Today, they will be preserved and re-natured, partly as historical natural heritage and partly as part of the CO2 limitation, as bogs collect CO2 and a breakdown causes further CO2 emissions.

The marsh on the southern side of the dyke - @Bjarke Petersen - Visit Rømø & Tønder.
@Ulrik Pedersen

An unforgiving nature.

A battle against the water

Ever since the 12th century, the first settlements in Marsken have been in an endless struggle against the water, which has repeatedly flooded areas where it was dry. From the Wadden Sea coast all the way to Tønder town.

Before the dikes, locks and pumping stations were built, Tøndermarsk was mainly under water in marshy areas, and people could not live here, crops could be grown or animals could graze here.

In 1556, the first dyke was built as protection against floods, this project was the first of several which seriously started the change of Tøndermarsken.

In 1929, the Lægan Pump Station was completed. The pumping station is one of four stations that daily dewater an area of 8,000 ha. Together, the four pumping stations can move up to 16,000 liters of water per second.

Although the Wadden Sea no longer floods the land behind the dykes, the community around Tønder cannot manage without the Lægan Pump Station, as low-lying fields, houses and towns will quickly be flooded by rainwater, as the water does not naturally flow into the sea in some areas.

Evacuation in 1976

In 1976, the sea dyke at Højer collapsed. This meant that many people had to be evacuated from the town of Højer and the many surrounding communities. The breaches in the dykes were the worst that had been seen in the life of the new dykes, and therefore they constructed, among other things, the advanced dyke in Højer in 1981, which to this day still stands as the first line of defense against the unforgiving storm surges.

Nature in the Marsh

Although the main purpose of the drainage was to provide space and safety for the residents of Marsken, it also had some positive consequences for the wildlife in Marsken, for example more breeding grounds and more food for the birds.

Margrethe Kog

When the extended dyke was built, Margrethe Kog – 800ha, Denmark's largest bird area with a 250ha saltwater lake behind the dyke – was created.


Located close to Vidåen on the Danish-German border, you will find a marshy bog with a large reed forest, where you can often experience Black Sol.

Hasberg Lake

Lake Hasberg lies on the border between Germany and Denmark, this lake is also known for Black Sun and many breeding bird species.

Other important lakes and wetlands include: Nørresø, Gammel Frederikskog, Siltoft, Rudbøl Sø and Bremsbøl Sø. Read a lot more about these places at: https://toendermarsken.dk/natur/fugle/

Birds in the Tønder marsh

Because the Tøndermarsh was drained and the many new areas with lakes, boils and wetlands were established, the growth of migratory and resting birds has increased significantly.

Various geese such as the bramble goose, short-billed goose, greylag goose and white goose fly to the Marsh in their thousands to breed, eat and be safe from predators.

Birds of prey that can be seen in the Marsh are peregrine falcon, peregrine falcon, griffon vulture, blue harrier and sea eagle.

Black Sun trip (watching large crowds of starlings)

One of the best-known bird phenomena in the Nordics is Black Sun, and in the Tøndermarsken you have the best conditions to experience Black Sun on a large scale. Up to 1.5 million starlings can gather in the same place in autumn, where they settle in the reed forest around some wetlands located in the dammed land, which is called kog.

There has often been a lot of activity around Magisterkogen and Hasberg Sø, which is right on the border between Germany and Denmark, it is often here that you see the very large flocks. In general, you can be lucky to experience Black Sol in many other places, just to a lesser extent.

We recommend going on a guided Black Sol tour, where you are almost guaranteed to see the birds.

A guided tour often costs between DKK 200/250, but here you also get up to a 3-hour guided tour by bus, where the guide talks about birds, the area and about Marsken in general.


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Handicap accessibility

Full accesseslightly

Level-free access, lift etc., which enable wheelchairs to get around.

Partially available

There are rooms/areas where wheelchair users cannot enter, but it is still possible to have a good experience.

Available with a helper or some walking function.

There is a step or other that means you need help in order to participate/enter.

Not available.

There is no lift, ramps or anything else that prevents wheelchairs from entering.

The accessibility assessment is based on a normal-sized wheelchair. If you use an extra-wide electric wheelchair or electric crosser, please contact the desired place of visit yourself. Likewise, there may be circumstances which mean that the availability for a period is not as described by us. A good idea is to always search for information on the website of the desired place to visit.