About the Pompeys Pillar National Monument
Pompeys Pillar National Monument is located on the banks of the Yellowstone River, 30 miles east of Billings, Montana’s largest city. The monument was established in 2001 to protect the only remaining physical evidence of the Lewis and Clark Expedition – Captain Clark’s signature carved into a 150-foot sandstone butte. In his journals, Clark named the Pillar “Pomp’s Tower” in honor of the infant son of Sacagawea, the Shoshoni woman who accompanied the expedition and contributed greatly to its success. The historic carving on the sandstone butte that Clark called a “remarkable rock” has inspired generations of visitors for more than 100 years. In 2010, more than 35,000 people visited this small site.