Lewis and Clark National Forest is located in west central Montana, United States. Spanning 2,912 square miles, the forest is managed as two separate zones. The eastern sections, under the Jefferson Division, is a mixture of grass and shrublands dotted with "island" pockets of forested areas. Here, cattle leases to local ranchers as well as timber harvesting are the norm. The western Rocky Mountain Division, which straddles the Continental divide, is managed chiefly for environmental preservation, as much of the land has been designated as wilderness. Forest headquarters are located in Great Falls, Montana. Local ranger district offices have been established in Choteau, Harlowton, Neihart, Stanford, and White Sulphur Springs.
The forest lands were defined and established by the federal government in 1897, following its Treaty of 1896 with the Blackfeet establishing their adjacent reservation. This forest is one of the oldest forest preserves in the U.S. The forest is named in honor of the members of the Lewis and Clark Expedition, which passed through the forest between 1804 and 1806 while exploring the Louisiana Purchase for President Thomas Jefferson.