Black Hills.

A landscape with a history.

Formed when rising magma pushed up the overlying crust without erupting at the surface, creating a broad dome. Erosion has since worn away much of the softer sedimentary rock that originally covered the dome, exposing older igneous and metamorphic rock at its core — a clear real-world illustration of the dome-mountain process described on the Mountain Building page.

What makes it remarkable

Geologically isolated from other major U.S. ranges — a relatively small, distinct uplift rather than part of a larger mountain belt.