Geologic drama abounds in Yellowstone Country. One of the most famous sites is striking Devils Tower, a 1,267-foot former volcanic neck near Sundance, Wyoming. And on the Yellowstone Highway west of Cody, you’ll see sinister outcroppings like The Holy City, Ford Rock, and Devil’s Backbone. For more information visit yellowstonecountry.org.
Vibrantly hued Plume Rock, near Rock Springs, is a dramatic monolith that juts from the desert floor. Pioneers following the Oregon Trail used Plume Rock as a landmark on their journey west.
The Buffalo Bill Cody Scenic Byway (parts of US 14, 16, and 20) passes astonishing rock formations along the North Fork of the Shoshone River. For more information visit yellowstonecountry.org.
Ayres Natural Bridge, between Douglas and Glenrock, is a rare rock arch with water flowing under it. For more information visit conversecountytourism.com; or call (307) 358-3532 or (307) 358-2950.
Split Rock, near the town of Jeffrey City, was a key landmark for early explorers, since it can be seen up to a full day’s journey from the east.
In Idaho, visit City of Rocks’s soaring granite columns—some as tall as 60 stories. And at Massacre Rocks State Park, near American Falls, high cliffs tower over the historic Oregon Trail.
Craters of the Moon National Monument, near Arco, is an 83-square-mile attraction with a stunning array of volcanic features and several rock arches.
In southern Idaho, Wind Tunnel Arch is a natural bridge that spans 33 feet. It is located in Jackknife Canyon, in the Lemhi Mountains north of Howe.
In eastern Montana, you’ll find caprocks, spires, and hoodoos at Makoshika State Park. Also visit the 50-foot-long Makoshika Natural Bridge near Glendive.
Inside Yellowstone National Park, take the 1.5-mile Natural Bridge Trail to view a 51-foot natural bridge.




how does a rock formation half a state away constitute itself as “within” Park boundaries?