21. Pompeys Pillar

Updated: August 7, 2020

In contrast to Lewis' troubled exploration of the Missouri and Marias, Clark's trip along the Yellowstone held pleasant surprises and visual wonders. He missed discovering Yellowstone Park by about 40 miles, but he discovered Pompeys Pillar. The pillar of sandstone was named "Pompy's Tower" on maps of the expedition. Clark named it in honor of Sacagawea's infant son, whom he'd nicknamed "Pompy," or "Little Pomp." On July 25, 1806, Captain Clark carved his name and the date on the rock.

Updated: August 7, 2020