Fort Fetterman was constructed in 1867 by the United States Army on the Great Plains frontier in Dakota Territory, approximately 11 miles northwest of present-day Douglas, Wyoming. Located high on the bluffs south of the North Platte River, it served as a major base for the start of several United States military expeditions against warring Native American tribes. T…Fort Fetterman was constructed in 1867 by the United States Army on the Great Plains frontier in Dakota Territory, approximately 11 miles northwest of present-day Douglas, Wyoming. Located high on the bluffs south of the North Platte River, it served as a major base for the start of several United States military expeditions against warring Native American tribes. The fort is listed on the National Register of Historic Places.