Geology explorer
Explore the Map
Each color is a different rock layer or deposit, mapped by geologists foot by foot across the park. Tap any spot to see what it is, how old it is and what to look for.
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Tap anywhere on the map
The layer cake
Read the Layers
The badlands are a stack of pages, oldest at the bottom. Tap a layer to read its chapter. Thicknesses are drawn roughly to scale for the North and South Units combined.
Where to see it
Where to See It
Pullouts and trails where the geology is front and center. Every stop links to the map and to directions.
Notes pop up, and can be read aloud, as you reach each stop.
Collecting rocks, fossils or petrified wood is illegal in national parks. Leave every stone for the next visitor. Bentonite clay turns slick after rain; stay on trails and off fresh slumps.
Sixty million years in nine chapters
How the Badlands Formed
Roosevelt arrived in 1883 to a landscape still being made. It still is.