Seven of Montana's Spellbinding Stone Structures

The Continental Divide runs through Montana, separating the mountains and glaciers on the west from rolling plains to the east. Much of the state is built on a bed of rock that dates back more than a billion years, to the Precambrian, or the earliest era in Earth's history. The geology of Montana has shaped the state, from the mountain ranges that draw hikers to Glacier and Yellowstone National Parks to mineral deposits that drew prospectors during the Gold Rush to the vast plains that have long supported hunting and agriculture.

1. GRANITE PEAK: Located in the Beartooth Mountains of southern...