Grejs River ( da, Grejs Å) is an approximately river in Vejle Municipality in

Denmark ) , song = ( en, "King Christian stood by the lofty mast") , song_type = National and royal anthem , image_map = EU-Denmark.svg , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of Denmark , establish ...

. Its source is Fårup Lake, south of the village of

Jelling Jelling is a railway town in Denmark with a population of 3,658 (1 January 2022), located in Jelling Parish, approximately 10 km northwest of Vejle. The town lies 105 metres above sea level. Location Jelling is located in Vejle municipal ...

. It starts by heading east through a

tunnel valley A tunnel valley is a U-shaped valley originally cut under the glacial ice near the margin of continental ice sheets such as that now covering Antarctica and formerly covering portions of all continents during past glacial ages. They can be as l ...

, then turns south to run through Grejs Valley ( da, Grejsdalen), the largest gorge in Denmark, until it reaches the city of

Vejle Vejle () is a city in Denmark, in the southeast of the Jutland Peninsula at the head of Vejle Fjord, where the Vejle River and Grejs River and their valleys converge. It is the site of the councils of Vejle Municipality ('' kommune'') and th ...

. North of Vejle, it splits into two branches, Omløbsåen ("Bypass River") and Mølleåen ("Mill River"). Omløbsåen runs west around the city centre to meet

Vejle River Vejle River ( da, Vejle Å, also called Sønderåen, "South River") is an approximately river in Vejle Municipality in Denmark. Its source is Engelsholm Lake near the village of Nørup. It first runs south to converge with the Egtved River near ...

, while Mølleåen flows through the city and empties into Vejle River just south of the city centre.

Grejs Valley

Grejsdalen set fra skaerbaekbakken mod Vejle - N Bredal

A section of the Grejs River runs through Grejs Valley ( da, Grejsdalen), the largest gorge in Denmark. The gorge is about long and deep. The gorge's cliffs are primarily

travertine Travertine ( ) is a form of terrestrial limestone deposited around mineral springs, especially hot springs. It often has a fibrous or concentric appearance and exists in white, tan, cream-colored, and even rusty varieties. It is formed by a p ...

and

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...

, some of which has been quarried as a building material. The traditional churches in nearby Hornstrup, Hover, and Jelling, as well as the modern Grejs Church, are built with Grejs Valley stone.

History

During the

Industrial Revolution The Industrial Revolution was the transition to new manufacturing processes in Great Britain, continental Europe, and the United States, that occurred during the period from around 1760 to about 1820–1840. This transition included going f ...

, Grejs River was used as a source of water power for about 14

watermill A watermill or water mill is a mill that uses hydropower. It is a structure that uses a water wheel or water turbine to drive a mechanical process such as milling (grinding), rolling, or hammering. Such processes are needed in the production of ...

s, which powered textile, paper, and metal factories. For example, Grejs Mølle Klædefabrik (Grejs Mill Textile Factory) was the country's largest private textile factory in 1830, employing 150 people. At the height of its activity around the turn of the twentieth century, the river had the highest concentration of industrial mills in the country. As of 2016, a

pumping station Pumping stations, also called pumphouses in situations such as drilled wells and drinking water, are facilities containing pumps and equipment for pumping fluids from one place to another. They are used for a variety of infrastructure system ...

was under construction at the confluence of Vejle River and the Omløbsåen branch of Grejs River in order to prevent high water levels in Vejle River and Vejle Fjord from backing up into Grejs River and causing floods.

Preservation

In 1929, of the upper Grejs River and the nearby Lerbæk Forest were set aside as a nature preserve, and in 2007, an additional were added to the preserve. The area was also designated a Natura 2000 nature conservation area. A section of the upper river near Fårup Lake has been restored. In the 2000s, some sections of the lower river in Vejle that had been culverted were daylighted.

References

{{reflist, 30em Rivers of Jutland Natura 2000 in Denmark