It starts by heading east through a tunnel valley, then turns south to run through Grejs Valley (Danish: Grejsdalen), the largest gorge in Denmark, until it reaches the city of Vejle.
The gorge is about 1 kilometre (0.62 mi) long and 50 to 70 metres (160 to 230 ft) deep.
[1] The gorge's cliffs are primarily travertine and limestone, some of which has been quarried as a building material.
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.
[6] A 2.3-kilometre (1.4 mi) section of the upper river near Fårup Lake has been restored.