Black Elk Peak, formerly known as Harney Peak, is the highest natural point in the U.S. state of South Dakota and the Midwestern United States. It lies in the Black Elk Wilderness area, in southern Pennington County, in the Black Hills. The peak lies 3.7 mi (6.0 km) west-southwest of Mount Rushmore. At 7,244 feet (2,208 m), it is the highest summit in the United States east of the Rocky Mountains. Technically, although not near the Rocky Mountains, Lost Mine Peak, in the Chisos Mountains of Texas, lies approximately 16 miles further east based on the measurement of longitude at 103°15'30"W and stands at 7,547 feet (2,300 m). Though part of the North American Cordillera, the Black Hills are generally considered to be geologically separate from the Rocky Mountains.