Dillon Perry made the discovery of the mystery rock while hunting for agates along the Yellowstone River near Greycliff.

Community members around the Flat Rock dam have become increasingly active in opposition to its potential removal.

Perry made the discovery of the mystery rock while hunting for agates along the Yellowstone River near Greycliff.

Kenneth Sims and other research scientists recently discovered that mafic volcanism of Henrys Fork Caldera -- located in ...