South Dakota

A collection of mammoth bones are embedded in tan sediment.

A waterfall cascades over a rocky ledge into a pool of water. An orange train is on tracks above the waterfall, with multi-story buildings in the background.

Falls of the Big Sioux River

A path leads down to a lake, lined with trees and grassy areas, where several people are gathered near water's edge.

A collection of mammoth bones are embedded in tan sediment.

Mammoth bones in situ at the Mammoth Site

Mammoth skeleton at the Mammoth Site

A bronze plaque with a relief portrait and text is mounted on a large, rough stone.

Mather Plaque in Wind Cave National Park

A narrow passage contains a vertical flow of white and orange mineral deposits.

Large specimen of cave bacon at Jewel Cave National Monument