Mount Rushmore Deadwood Custer State Park Black Hills National Forest Badlands National Park Wind Cave National Park 1880 Train Hiking Trails Bear Country Crazy Horse Devils Tower Iron Mountain Needles Highway Spearfish Canyon Mickelson Trail Reptile Gardens BADLANDS NATIONAL PARK Secreted beneath one of our country’s oldest national parks and one of its few remaining intact prairies is one of the world’s longest caves, Wind Cave.