Pompeys Pillar National Monument

Bureau of Land Management, Montana.

Remember your OUTDOOR ETHICS when enjoying your public lands. Please RECREATE RESPONSIBLY.


Pompeys Pillar National Monument encompasses 51 acres on the banks of the Yellowstone River with a massive sandstone outcrop covering about 2 acres at its base and rising 120 feet high toward Montana's Big Sky. The monument's premier location at a natural ford in the Yellowstone River, and its geologic distinction as the only major sandstone formation in the area, have made Pompeys Pillar a celebrated landmark and outstanding observation point for more than eleven thousand years of human occupation. Hundreds of markings, petroglyphs, and inscriptions left by visitors including William Clark and the Lewis and Clark Expedition have transformed this geologic phenomenon into a living journal of the American West. 

Know Before You Go

2023 Hours

Main Gate (May-Sept.): 8:30 AM - 4:30 PM

Interpretive Center (May-Sept.): 9 AM - 4 PM 

NOTE: Even when the Monument is closed, visitors may still walk into the site during daylight hours. The walk from the gates to the Pillar is about 3/4 mile. Special arrangements can be made during the off-season for school programs and other special events.

Available Facilities

The interpretive center, restrooms, parking lot and day use area are fully accessible.


Pets must be on a leash at all times.

Be Respectful!

Please respect the heritage of Pompeys Pillar National Monument. Do not deface any tree, shrub, rock, or ancient Indian artifact. Do not touch petroglyphs or remove any artifact. Not only is this illegal, but it erases evidence of past generations and deprives others of the knowledge about these sites.

Partnerships: Friends of Pompeys Pillar

The Friends of Pompeys Pillar provides substantial and much needed support for the Monument. This 200-member, nonprofit organization supplies more than 35 volunteers to assist visitors at the site and to operate the interpretive center. Profits from this enterprise assist with operation of the Monument. More than 2,500 hours of volunteer time are donated each year.

Helpful Links

Nearby Activities


The area is easily accessible from Interstate 94, using exit 23, or from State Highway 312. The monument is 25 miles east of Billings, Montana

Photo Gallery