Congress of the United States


Date of this Version



Published by Congressional Research Service,, RL31447


Congress enacted the Wilderness Act in 1964. This Act created the National Wilderness Preservation System, reserved to Congress the authority to designate wilderness areas, and directed the Secretaries of Agriculture and of the Interior to review certain lands for their wilderness potential. The Act also designated 54 wilderness areas with 9 million acres of federal land. Congress began expanding the Wilderness System in 1968, and today, there are 708 wilderness areas, totaling more than 107 million acres, in 44 states. Numerous bills to designate additional areas and to expand existing ones are introduced and considered in every Congress.

The Wilderness Act defined wilderness as an area of generally undisturbed federal land, but did not establish criteria or standards to determine whether an area should be designated, because of differing perceptions of wilderness and because of the varying purposes of wilderness. In general, wilderness areas are undeveloped, and commercial activities, motorized access, and roads, structures, and facilities are generally prohibited in wilderness areas. However, in response to conflicting demands, Congress has granted both general exemptions and specific exceptions to the general standards and prohibitions.

The federal government owns about 29% of the land in the United States, although the proportion in each state varies widely. Four federal agencies — the Bureau of Land Management, National Park Service, and Fish and Wildlife Service in the Department of the Interior and the Forest Service in the Department of Agriculture — manage most of the federal lands. These agencies manage the 107 million acres of designated wilderness, as well as many other lands. They are also protecting lands as possible additions to the Wilderness System, and are reviewing the wilderness potential of additional lands.

In total, more than 17% of all federal land, and nearly 5% of all land in the United States, has been designated as wilderness. Alaska, because of its size and relatively pristine condition, dominates wilderness statistics — more than 53% of designated wilderness is in Alaska. In total, nearly 16% of all land (federal, state, private, and other) in Alaska has been designated as wilderness. In contrast, 3% of all land in the United States outside Alaska has been designated as wilderness.