Henry's Lake National Forest was established as the Henry's Lake Forest Reserve by the U.S. Forest Service in Idaho on May 23, 1905 with 798,720 acres (3,232.3 km2).
It became a National Forest on March 4, 1907.
On July 1, 1908 the entire forest was combined with a portion of Yellowstone National Forest to establish Targhee National Forest and the name was discontinued.
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