1802 Louisiana Purchase - President Jefferson commissions Lewis and Clark to explore the Missouri drainage to the Pacific.

1820-30's Peak of fur trade; beaver population declines dramatically. 1862 Under President Lincoln, the Homestead Act was passed, making 160 acres of public domain available to every family willing to work the land.

1865 Yosemite becomes the first reserve removed from the public domain, placed under jurisdiction of the State of California for protection as a park.

1872 Yellowstone becomes the first National Park.

1878 John Wesley Powell, in the "1878 Report on the Lands of the Arid Region of the United States", calls for more realistic systematic planning for the West and its resources, including the need for public water storage and resource conservation.

1891 The first Forest Reserve System was created.

1892 Sierra Club formed by John Muir and 26 San Francisco residents "to explore, enjoy, and render accessible the mountain regions of the Pacific Coast...and enlist the support and cooperation of the people and the government in preserving the forests and other natural features of the Sierra Nevada".

1896 Frederick Jackson Turner asserts, in The Significance of the American Frontier in American History, that the frontier no longer exists. Also discusses the role of wilderness in fostering individualism, independence, and thus self-government.

1897 Congress passes the Forest Management Act, opening the forests to timber cutting, mining and grazing. This clarified the difference between preservation and conservation, a polarized view of public resources that still plagues land-use debates.

1905 Forest Reserves transferred from Department of Interior to the Department of Agriculture, thereby creating the Forest Service. A multiple-use policy was initiated under Gifford Pinchot, the first Forest Service Chief.

1916 National Park Service Organic Act was passed, creating the Park Service for the administration of the National Parks.

1919 Arthur Carhart, a Forest Service Landscape Architect, recommends that the Trappers Lake area in Colorado not be developed for summer homes, but allowed to remain wild. His plan is approved.

1924 Aldo Leopold, Forester and ecologist, persuades the Forest Service to protect the 574,000 acre Gila National Forest of New Mexico for wilderness recreation.

1926 W.B. Greeley, Chief Forester of the U.S. Forest Service, directs preparation of an inventory of all "de facto" wilderness in the national forests.

1929 The Forest Service issues the L-20 regulation to protect some of its "primitive" areas from commercial development until management plans are developed.

1930 Congress enacts the Shipstead-Newton-Nolan Act to protect over 1 million acres in the Superior Primitive Area in Minnesota--the first federal law in American history to protect a wilderness area.

1934 The Taylor Grazing Act is passed.

1935 The Wilderness Society is formed, led by Bob Marshall, Aldo Leopold and others.

1939 The Forest Service supplants the L-20 regulations with the "U Regulations". Former "primitive" are reclassified as "Wilderness," "wild" or "roadless," depending on size.

1946 Bureau of Land Management is created by the joining of the Grazing Service and General Land Office.

1950 Conservationists work to prevent construction of a dam at Echo Park in Dinosaur National Monument.

1955 Howard Zahniser, Executive Director of the Wilderness Society, writes first draft of a Wilderness Bill. This Bill would designate lands to be protected from any form of resource extraction.

1956 Senator Hubert Humphrey introduces the first Wilderness bill in the U.S. Senate. Congress preserves Echo Park by passing a bill that prevents any dam from being built in National Parks or Monuments.

1963 U.S. Senate passes the Wilderness Bill.

1964 House of Representatives passes the Wilderness Bill. President Johnson signs the Wilderness Act at a White House garden ceremony on September 3.

1976 Federal Land Policy and Management Act (FLPMA) passed repealing the Homestead Act and granting the Bureau of Land Management the authority it needed to fully manage its public lands.