Roadside Geology Markers Glacial Lake Missoula Lewis Overthrust Fault Egg Mountain Cliffs High and Steep: Adel Mountain Volcanics Prickly Pear Canyon Elkhorn Volcanoes & Boulder Batholith New World: Tertiary Mammals Square Butte & Shonkin Sag Judith River Formation Bearpaw Shale & Inland Seaway Hellcreek Formation #2 Medicine Rocks Hellcreek Formation #1 Hellcreek Formation #1 Beartooth Plateau Great Inland Ocean Lone Mountain Shore of an Ancient Sea Kootenai Falls & the Belt Supergroup Welcome to Dinosaur Country A Pleistocene Wonderland Coal, Oil, and Natural Gas Island on the Plains - The Bears Paw Mountains Hepburn's Mesa The Shining Mountains Mountains on the Move - The Bitteroot and Sapphire Mountains The Ice Ages Red-Capped Hills of Eastern Montana Black Gold A Lost World - Precambrian Belt Rocks Passage Through Time - The Jefferson River Canyon Landslide Butte Beartooth Plateau Bearpaw Shale & Inland Seaway Cliffs High and Steep: Adel Mountain Volcanics Egg Mountain Elkhorn Volcanoes & Boulder Batholith Glacial Lake Missoula Great Inland Ocean Hellcreek Formation #1 Hell Creek Formation #2 Judith River Formation Lewis Overthrust Fault Medicine Rocks New World: Tertiary Mammals Prickly Pear Canyon Square Butte & Shonkin Sag Hell Creek Formation #2 link to hellcreek