Atnsjømyrene is a large mire complex dominated by flat fens, which also includes pools, ponds and parts of the Atnsjøen lake. A characteristic of the Site is its nutrient-poor vegetation, though  willow and birch forests are common along the watercourses and mire edges. The mixture of different wetland types makes the Site a valuable breeding area for waterbirds, and especially ducks and waders. The mires are important water reservoirs and offer flood protection during periods of snow melt and heavy precipitation. The Site is used for hunting, sports fishing, berry picking and sheep grazing. It is an important monitoring Site, chosen in 1986 as a reference inland watercourse, where scientists can monitor long-term variations in natural processes and ecosystems that are almost untouched by technical alterations. The restoration of the Site is planned – trenches dug for agricultural reasons such as peat harvesting will be filled, and dams will be built to increase water retention.