The Wilderness Act of 1964 (Pub.L. 88–577) was written by Howard Zahniser of The Wilderness Society. It created the legal definition of wilderness in the United States, and protected 9.1 million acres (36,000 km²) of federal land. The result of a long effort to protect federal wilderness and to create a formal mechanism for designating wilderness, the Wilderness Act was signed into law by President Lyndon B. Johnson on September 3, 1964 after over sixty drafts and eight years of work.
The Wilderness Act is well known for its succinct and poetic definition of wilderness:
“A wilderness, in contrast with those areas where man and his own works dominate the landscape, is hereby recognized as an area where the earth and community of life are untrammeled by man, where man himself is a visitor who does not remain.”
When Congress passed and President Lyndon Johnson signed the Wilderness Act on September 3, 1964, it created the National Wilderness Preservation System. The initial statutory wilderness areas, designated in the Act, comprised 9.1 million acres (37,000 km²) of national forest wilderness areas in the United States of America previously protected by administrative orders. The current amount of areas designated by the NWPS as wilderness totals 757 areas encompassing 109.5 million acres of federally owned land in 44 states and Puerto Rico (5% of the land in the United States).
California Considerations 
California politicians were concerned about maintaining the viability of plans for a highway or tunnel connecting the Eastern Sierra and the San Joaquin Valley. These plans centered on the Minaret Summit area as the distance between the end of Minaret Road, which runs northeast into the Sierras from North Fork, California, and the end of the Reds Meadow Road, running west from Mammoth Lakes, California is less than 10 miles. The Act excluded an area southwest of Minaret Summit to create a corridor for this possibility.
Today, the Wilderness System comprises over 106 million acres (429,000 km²) involving federal lands administered by four agencies:
|The National Wilderness Preservation System:
Area Administered by each Federal Agency (July 2004)
|Agency||Wilderness area||Agency land
|National Park Service||43,616,250 acres (176,508 km²)||56%|
|U.S. Forest Service||34,867,591 acres (141,104 km²)||18%|
|U.S. Fish and Wildlife Service||20,699,108 acres (83,766 km²)||22%|
|Bureau of Land Management||6,512,227 acres (26,354 km²)||2%|
|Total||107,436,608 acres (427,733 km²)||16%|
Legal framework 
The Wilderness Act will be chosen from existing federal land and by determining which areas are considered to have the following criteria: (1) minimal human imprint, (2) opportunities for unconfined recreation, (3) at least five thousand acres, and (4) to have educational, scientific, or historical value. Additionally, areas considered as Wilderness should have no enterprises within them or any motorized/mechanized devices (e.g.; vehicles, motorbikes, or bicycles).
When Congress designates each wilderness area, it includes a very specific boundary line—in statutory law. Once a wilderness area has been added to the System, its protection and boundary can only be altered by another act of Congress. That places a heavy burden on anyone who, all through the future, may propose some change.
The basics of the program set out in the Wilderness Act are straightforward:
- The lands protected as wilderness are areas of our public lands.
- Wilderness designation is a protective overlay Congress applies to selected portions of national forests, parks, wildlife refuges, and other public lands.
- Within wilderness areas, the Wilderness Act strives to restrain human influences so that ecosystems [the Wilderness Act, however, makes no specific mention of ecosystems] can change over time in their own way, free, as much as possible, from human manipulation. In these areas, as the Wilderness Act puts it, “the earth and its community of life are untrammeled by man”—untrammeled meaning the forces of nature operate unrestrained and unaltered.
- Wilderness areas serve multiple uses. But the law limits uses to those consistent with the Wilderness Act mandate that each wilderness area be administered to preserve the “wilderness character of the area.” For example, these areas protect watersheds and clean-water supplies vital to downstream municipalities and agriculture, as well as habitats supporting diverse wildlife, including endangered species, while logging and oil and gas drilling are prohibited.
- Along with many other uses for the American people, wilderness areas are popular for diverse kinds of outdoor recreation—but without motorized or mechanical vehicles or equipment. Scientific research is also allowed in wilderness areas, as long as it is non-invasive.
- The Wilderness Act was reinterpreted by the Administration in 1986 to ban bicycles from Wilderness areas, which led to the current vocal opposition from mountain bikers to the opening of new Wilderness areas.
- The Wilderness Act allows certain uses (e.g.; resource extraction, grazing, etc.) which existed before the land became wilderness to be grandfathered in, permitting them to continue to take place although the area that was designated as wilderness typically would not concede such uses. Specifically, mining, grazing, water uses, or any other uses that don’t significantly impact the majority of the area, can remain in some degree.
When the Wilderness Act was passed, it ignored lands managed by the Bureau of Land Management because of uncertainty of policy makers surrounding the future of those areas. The uncertainty was clarified in 1976 with the passing of the Federal Land Policy and Management Act, which stated that land managed by the Bureau of Land Management would remain federally owned and, between March 1978 and November 1980, would be reviewed to possibly be labelled as Wilderness.
Much opposition exists surrounding wilderness designation. One argument is that the criteria set forth to determine what is wilderness is vague and open to interpretation. For example, part of the criterion says that wilderness must be roadless. The definition given for roadless is “the absences of roads which have been improved and maintained by mechanical means to insure relatively regular and continuous use.” However, there have been added sub-definitions that have, in essence, made this standard unclear and open to interpretation.
Future legislation 
Congress considers additional proposals every year, some recommended by federal agencies and many proposed by grassroots conservation and sportsmen’s organizations.
Congressional bills are pending to designate new wilderness areas in Utah, Colorado, Washington, California, Virginia, Idaho, West Virginia, Montana and New Hampshire. Grassroots coalitions are working with local congressional delegations on legislative proposals for additional wilderness areas, including Vermont, southern Arizona, national grasslands in South Dakota, Rocky Mountain peaks of Montana, Colorado and Wyoming. The U.S. Forest Service has recommended new wilderness designations, which citizen groups may propose to expand.
See also 
- U.S. Wilderness Area
- List of U.S. Wilderness Areas
- Natural heritage
- Eastern Wilderness Act of 1974
- Boundary Waters Canoe Area Wilderness Act of 1978
- Alaska National Interest Lands Conservation Act of 1980
- California Wilderness Act of 1984
- Northern California Coastal Wild Heritage Wilderness Act of 2006
- Omnibus Public Land Management Act of 2009
- Skelton, George (1997-07-28). "The Man in the White Hat Who Saved the Sierra". Los Angeles Times.
- Table from The Enduring Wilderness: Protecting Our Natural Heritage through the Wilderness Act (Fulcrum Publishing, 2004). Wilderness area by agency from www.wilderness.net. For consistency, all data used for percentage calculation are from Federal Land Management Agencies: Background on Land and Resource Management (Washington, D.C.: Congressional Research Service, RL30867, February 2001)
- Durrant, Jeffrey, Struggle Over Utah's San Rafael Swell : Wilderness, National Conservation Areas, and National Monuments,Tucson: University of Arizona Press, 2007. Print.
- Turner, James Morton (2012). The Promise of Wilderness: American Environmental Politics since 1964. Seattle: University of Washington Press. ISBN 978-0295991757.
- Dant, Sara. “Making Wilderness Work: Frank Church and the American Wilderness Movement.” Pacific Historical Review 77 (May 2008): 237-272.
- Doug Scott (August 15, 2004). The Enduring Wilderness: Protecting Our Natural Heritage through the Wilderness Act. Fulcrum Publishing. ISBN 1-55591-527-2.
- "The Wilderness Act of 1964." 
- Jeffrey 0. Durrant (2007). Struggle Over Utah's San Rafael Swell : Wilderness, National Conservation Areas, and National Monuments. Tucson: University of Arizona Press. ISBN 0-8165-2669-9.
- James Morton Turner (2012). The Promise of Wilderness: American Environmental Politics since 1964. Seattle: University of Washington Press. ISBN 978-0295991757.
- The Wilderness Society (political advocacy)
- Listen to President Johnson's remarks at the signing of the Wilderness Act on September 3, 1964
- Full text of the Wilderness Act
- Overview of other wildnerness-related legislation
- Campaign for America's Wilderness (political advocacy)
- Protect California's Remaining Wilderness (political advocacy)
- Utah Wilderness Coalition (political advocacy)
- Californians for Western Wilderness (political advocacy)
- America's Redrock Wilderness Act - Library of Congress