Badlands National Park is an American national park in southwestern South Dakota. The park protects 242,756 acres of sharply eroded buttes and pinnacles, along with the largest undisturbed mixed grass prairie in the United States. The National Park Service manages the park, with the South Unit being co-managed with the Oglala Lakota tribe.

The Pine Ridge Indian Reservation, also called Pine Ridge Agency, is an Oglala Lakota Indian reservation located in the U.S. state of South Dakota, with a small portion of it extending into Nebraska. Originally included within the territory of the Great Sioux Reservation, Pine Ridge was created by the Act of March 2, 1889, 25 Stat. 888. in the southwest corner of South Dakota on the Nebraska border. It consists of 3,468.85 sq mi (8,984 km2) of land area and is one of the largest reservations in the United States.