The protected areas of North Carolina cover roughly 3.8 million acres, making up 11% of the total land in the state. 86.5% of this protected land is publicly owned and is managed by different federal and state level authorities and receive varying levels of protection. Some areas are managed as wilderness while others are operated with acceptable commercial exploitation. The remainder of the land is privately owned, but willingly entered into conservation easement management agreements, or are owned by various nonprofit conservation groups such as the National Audubon Society and The Nature Conservancy. North Carolina contains 1 National Park, and various other federally owned protected land including 2 National Seashores, 5 National Forests, 12 Wildlife Refuges, and the southern half of the Blue Ridge Parkway. North Carolina has an extensive state park system of 42 open units, 35 of which are state parks, 4 that are recreation areas, and 3 staffed state natural areas, along with other designated units managed by the North Carolina Department of Natural and Cultural Resources.