Färnebofjärden, previously known as Dalälven-Färnebofjärden, includes Färnebofjärden National Park and Gysinge and Ålbo Nature Reserves. The River Dalälven runs in a flat and open landscape, where it widens and forms a series of broad and shallow lakes. Short, often multi-branched rapids separate the lakes. It is a rare example in the European Boreal region of a near-natural river system with regular flooding. Its important habitats include alluvial forests, exposed river bottoms with fine-grained soils, rapids and open fens along the river. The unexploited rapids, along with the limited forestry and small human population in the immediate vicinity of the Site, give an impression of untouched wilderness. Situated at the transition between the vegetation types of northern and southern Sweden, the Site has a rich diversity of mires, riverside meadows, birch and alder fens, marsh meadows, peat bogs, and shore fens. Flooding is common, and flood control is an important function of the Site. The fauna is diverse, from the many birds and fish species, to the largest population in Sweden of the mosquito Aedes rossicus. Because of the wilderness character of the area, and its fauna and landscape, it is well known for birdwatching, hiking, canoeing, and fishing.