Bison, elk, and other wildlife roam the rolling prairie grasslands and forested hillsides of one of America's oldest national parks. Beneath the remnant island of intact prairie lies Wind Cave, one of the longest and most complex caves in the world. Named for barometric winds at its entrance, this maze of passages contains boxwork, a unique formation rarely found elsewhere.

Photo: NPS Photo

Photo: NPS Photo

Photo: NPS Photo

Photo: NPS Photo / Dan Roddy

Buffalo Gap, South Dakota · USA