English: Photograph by the Public Lands Institute. Site: Black Hills National Forest, South Dakota. Managed by proclaimed 1897 as Black Hills Forest Reserve. Geological age: ~1,715 Mya Paleoproterozoic Harney Peak granite at the core; ~2,500 Mya Precambrian schist and quartzite; encircled by Paleozoic limestone and Cretaceous shale (Paleoproterozoic). Hydrology: The Black Hills form the headwaters divide between the Cheyenne River (southern and eastern drainages) and the Belle Fourche River (northern drainage), both Missouri River tributaries. Indigenous territories: Lakota (Thitunwan Oyate), the seven bands of the Oceti Sakowin: Oglala, Sicangu (Brule), Miniconjou, Hunkpapa, Sans Arc, Oohenunpa, and Sihasapa; Cheyenne (Tsitsistas/Suhtai); Arapaho (Hinono'eino); earlier presence of Crow, Kiowa, and Arikara; the Black Hills are Paha Sapa / He Sapa (heart of everything that is) to the Lakota, central to spirituality, ceremony, and subsistence; the Treaty of Fort Laramie (1868) guaranteed the Black Hills and all of present South Dakota west of the Missouri River for exclusive Sioux occupation; gold discovered during the 1874 Custer Expedition triggered an illegal invasion; the Act of February 28, 1877 stripped the Black Hills from the Sioux without the required three-fourths adult male consent; United States v. Sioux Nation of Indians (1980) ruled this an unconstitutional taking; the Sioux declined over $1 billion in compensation and continue to demand land return.