The Järleån valley is several hundred thousand years old, and was formed before the glacial period. When the most recent ice sheet melted, virtually the entire valley was below sea level. The retreating ice deposited thick layers of gravel, sand and clay in the bottom of the valley and the River Järleån winds its way through these layers today.
In the past, crops have been grown on these moraine soils, but today the land is used for pasture. On more inaccessible slopes and in ravines, the vegetation comprises deciduous and mixed forest.
Plant and animal life
The fine-grained and nutrient-rich soil promotes a wide variety of plant species. This is shown, for example, by the large number of different broadleaved trees. In the parts of the nature reserve that were previously used for hay making and pasture, the most common trees are grey alder and ash. Some individual trees of very old and thick ash and birch remain from the hay making period. Another common tree along the river Järleån is the bird cherry, which blooms early in the spring.
The vegetation is lush. More unusual plants found in the reserve include mezereon, common toothwort, lungwort and field horsetail. In the spring, the wood anemone blooms in vast numbers in the deciduous forest and, in the summer, the globeflower is prominent amongst the flowering plants.
Birds that live in the nature reserve include goldeneye, goosander, dipper and grey wagtail, and kingfishers are seen in some years. Beavers are common and, in recent years, otters have been seen in the river.
The Långforsen rapids are impressive during periods of high water. Water flow is at its maximum during the spring flood, but even after a rainy period later in the year, large quantities of water can race through the rapids.
The effect of running water on landforms is noticeable along the River Järleån. On the outsides of the bends, the banks are being eroded, creating river cliffs. The cliffs are then undermined and collapse into the river, taking with them trees and bushes, forming bare areas and landslip scars. On the insides of the bends, gravel, sand and fine-grained material is deposited, forming new land.
As early as the mid-16th century, there was an ironworks by the River Järleån. Over the subsequent centuries, the Järleån valley became the most important centre for iron-smelting in the Noraskog iron district, with furnaces and forges on three different dams.
Ironworking in the area continued until the 1920s, but now only ruins remain, along with slag piles and other remains. Järle mill, which was still in operation in the 1970s, is preserved in its original condition.
When to visit Järleån?
The rapids are at their most impressive in early spring. Later in the spring and in early summer, the flowers are worth seeing and birdsong is at its height. There are a number of picnic spots by the river.
How to get there
Turn off road 50 towards Yxe, immediately north of the Noraavfarten junction. In Yxe, follow the road towards Hammarby. The nature reserve lies along the road. The second car park is most suitable.
In the nature, you are not permitted to:
- damage ground and plants
- pick flowers
- disturb animals
- have dogs unleashed
- light fires except for in designated places
- park a caravan
- drive a motorboat
- drive vehicles or park anywhere but in the car parks