Cheyenne National Forest was established in Wyoming by the U.S. Forest Service on July 1, 1908 with 617,932 acres (2,500.68 km2) from part of Medicine Bow National Forest and all of Crow Creek National Forest. On July 1, 1910 a portion was eliminated and the remainder renamed Medicine Bow National Forest.
References
Cheyenne National Forest Wikipedia(Text) CC BY-SA