Pompeys Pillar National Monument features a striking sandstone formation with the only remaining physical evidence of the Lewis and Clark Expedition in Montana, offering unique historical and hiking experiences.
Pompeys Pillar National Monument is located in south-central Montana along the Yellowstone River, near the town of Billings. The centerpiece is a 150-foot sandstone pillar rising above the surrounding plains, notable for William Clark's carving of his name in 1806 during the Lewis and Clark Expedition. This carving marks the only physical evidence on the expedition route in Montana, making the site an important cultural and historical landmark. The pillar itself is composed of sedimentary rock formed from river deposits millions of years ago and hosts a variety of native plants on its base, including grasses and shrubs typical of the northern Great Plains. Wildlife such as mule deer, hawks, and various songbirds can often be observed in the area. Visitors can explore a self-guided nature trail that circles the pillar, featuring interpretive signs about the geology, ecology, and expedition history, as well as a visitor center with exhibits and educational programs. Recreational activities primarily include hiking, photography, and historical appreciation. The monument’s location along the Yellowstone River adds to its scenic appeal and provides a habitat for riparian species. Pompeys Pillar offers an accessible and educational outdoor experience, with paved parking, picnic areas, and accessible pathways, making it suitable for families and history enthusiasts. The site’s unique combination of natural beauty and historical significance draws thousands of visitors annually.
William Clark's original inscription carved into the sandstone pillar
Scenic views of the Yellowstone River valley from the top of the pillar
Interpretive trails with educational signage about Lewis and Clark history
Visitor center featuring historical exhibits and local flora/fauna information
A 150-foot high sandstone pillar formed from sediment deposited by ancient rivers, ideal for climbing and historical exploration.
The only physical evidence left by the Lewis and Clark Expedition in Montana, carved by Clark himself in 1806.
Panoramic views of the surrounding river valley and rolling plains can be seen from atop the pillar and along the trails.