badlands national park
rugged, eroded area of buttes, saw-toothed divides, and gullies in southwestern South Dakota, U.S. It was established as a national monument in 1939 and designated a national park in 1978. It lies in a semiarid high-plains region mostly between the Cheyenne and White rivers, 40 miles (65 km) southeast of Rapid City, and occupies an area of 379 square miles (982 square km).
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