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The overlook at Pompeys Pillar National Monument.
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  • States:
    Montana

Experience the view Capt. William Clark witnessed more than 200 years ago.

Pompeys Pillar stands out on both the landscape of eastern Montana and in U.S. history. The 46-meter sandstone outcrop along the banks of the Yellowstone River is the site of the only known physical evidence along the path of the expedition Clark made with Meriwether Lewis from 1804 to 1806. On his return trip to St. Louis, Clark noted the formation in his expedition journal: “This rock I ascended and from its top had a most extensive view in every direction on the Northerly Side of the river high romantic Clifts approach & jut over the water for Some distance both above and below ... I marked my name and the day of the month and year." Clark named the formation Pomp’s Tower, after the nickname given to the infant son of Sacagawea, a Shoshone woman who helped guide them.

Getting There

Located along the Lewis and Clark National Historic Trail, the sandstone butte was designated as a National Historic Landmark in 1965 and established as a National Monument in 2001. The 530-square-meter interpretive center opened in 2006.

Pompeys Pillar National Monument is about 25 miles east of Billings, Montana. The area is easily accessible from Interstate 94, using exit 23, or from Montana Highway 312. The interpretive center, restrooms, parking lot and day use area are fully accessible. The Interpretive center is open from 9 a.m. to 6 p.m. daily. Check with the Pompeys Pillar Historical Association for hotel and motel accommodations nearby.

Pompeys Pillar National Monument, a sandstone butte

Pompeys Pillar National Monument, a sandstone butte
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Along the Riverfront

Make sure you wind your way to the sandstone butte by following the Riverwalk, representing the Yellowstone River. The Riverwalk begins in the parking lot and meanders through the interpretative center to the base of Pompeys Pillar. Signs along the path quote from Clark's journals and tell of the party’s experiences from their entry on the Yellowstone on July 15, 1806, to their encampment at the confluence of the Yellowstone and Missouri Rivers on Aug. 3.

Enjoy a picnic or relax in the shade of cottonwood trees at the day use area next to the Yellowstone River.

Countryside surrounding the Yellowstone River

Countryside surrounding the Yellowstone River
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Look at the Signature

Take a look at Clark’s name etched in the rock more than 200 years ago. Be aware that there are numerous other cultural, historic and natural resources that are vital to the monument and should be treated with respect.

Day use fees are less than $10 per vehicle. There is no separate fee for the interpretive center. All fees are returned to the site and used to maintain and improve the facility. All valid federal recreation passes are honored at the site.

The initials of Capt. William Clark, etched more than 210 years ago

The initials of Capt. William Clark, etched more than 210 years ago
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Did You Know?

You can stand on the boardwalk atop Pompeys Pillar and identify the same landmarks Clark used to describe the site over 200 years ago. Clark’s signature was not the first marking made on Pompeys Pillar. He inscribed his name next to Native American pictographs and petroglyphs, some of which can still be seen today.

The Crow Indians called the pillar the place where the mountain lion lives. This was because there is a rock on the north face of the pillar that resembles the head of a mountain lion.