thumb|An unusual specimen of [[calcite, densely intergrown with grains of sand. Collected from Rattlesnake Butte in Jackson County. Size: 6.9 x 5.4 x 3.9 cm.]]
thumb|right|Jackson County sign on [[Interstate 90]]
Jackson County is a county in the U.S. state of South Dakota. As of the 2020 census, the population was 2,806. Its county seat is Kadoka. The county was created in 1883, and was organized in 1915. Washabaugh County was merged into Jackson County in 1983.
Geography
The terrain of Jackson County consists of mountains rising from rolling hills. The ground is arid and carved with drainages. The White River flows eastward, cutting a meandering channel through the central part. The terrain generally slopes to the NE; its highest point is a ridge near the SW corner, at ASL.
Jackson County has a total area of , of which is land and (0.4%) is water. About 57 percent of its land, the portion south of White River, is on the Pine Ridge Indian Reservation. The county includes the easternmost portion of Badlands National Park. thumb|Badlands National Park near Interior
South Dakota's eastern counties (48 of 66) observe Central Time; the western counties (18 of 66) observe Mountain Time. Jackson County is the easternmost of the state's counties to observe Mountain Time.
Major highways
- 20px Interstate 90
- 20px U.S. Highway 14
- 20px South Dakota Highway 44
- 20px South Dakota Highway 63
- 20px South Dakota Highway 73
- 23px South Dakota Highway 377
Adjacent counties
- Haakon County – north
- Jones County – northeast (observes Central Time)
- Mellette County – east (observes Central Time)
- Todd County
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The population density was . There were 1,064 housing units, and there were 887 households, including 637 families residing in the county.
Of those households, 39.3% had children under the age of 18 living with them and 25.1% had a female householder with no spouse or partner present. About 24.7% of all households were made up of individuals and 10.1% had someone living alone who was 65 years of age or older.
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See also
- National Register of Historic Places listings in Jackson County, South Dakota