Wilderness or wildland is a natural environment on Earth that has not been significantly modified by civilized human activity. It may also be defined as: "The most intact, undisturbed wild natural areas left on our planet—those last truly wild places that humans do not control and have not developed with roads, pipelines or other industrial infrastructure."
Some governments establish them by law or administrative acts, usually in land tracts that have not been modified by human action in great measure. The main feature of them is that human activity is restricted significantly. These actions seek not only to preserve what already exists, but also to promote and advance a natural expression and development. Wilderness areas can be found in preserves, conservation preserves, National Forests, National Parks and even in urban areas along rivers, gulches or otherwise undeveloped areas. These areas are considered important for the survival of certain species, biodiversity, ecological studies, conservation, solitude, and recreation. Wilderness is deeply valued for cultural, spiritual, moral, and aesthetic reasons. Some nature writers believe wilderness areas are vital for the human spirit and creativity. They may also preserve historic genetic traits and provide habitat for wild flora and fauna that may be difficult to recreate in zoos, arboretums or laboratories.
The word wilderness derives from the notion of "wildness"—in other words, that which is not controlled by humans. The mere presence or activity of people does not disqualify an area from being "wilderness." Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered "wild." This way of looking at wilderness includes areas within which natural processes operate without human interference.