Lewis and Clark Yellowstone River Journey

By editor

Billings, Yellowstone County, Montana

On a summer day 218 years ago, Captain William Clark guided his party down the Yellowstone River opposite this very point. The date was July 24, 1806. Having parted ways with Meriwether Lewis at Traveler’s Rest in the Bitterroot Valley on July 3, Clark led the southern detachment of the returning Lewis and Clark Expedition--a group of twelve souls, including Sacagawea, her husband Toussaint Charbonneau, and their infant son Jean Baptiste. While Lewis chose the northern mountain route back to the Mandan villages, Clark charted the course downstream along the Yellowstone, a river whose swift, clear waters and towering sandstone cliffs he would come to know intimately.

The journey to this riverine corridor began weeks earlier. Clark’s party crossed the Continental Divide at Gibbon Pass, a saddle carved by the relentless forces of ice and water over millennia. From there, they descended the Gallatin River--a tributary named for Albert Gallatin, then Secretary of the Treasury--until they reached the Three Forks of the Missouri River. This confluence marked a critical junction where the Madison, Jefferson, and Gallatin Rivers merge to form the mighty Missouri. After a brief overland trek, the explorers reached the Yellowstone River near the site of present-day Livingston on July 15.

At this juncture, they constructed two dugout canoes from hollowed cottonwood trunks, a practice refined from native techniques. The river’s character in midsummer revealed itself in the crystalline clarity of its waters, flowing with a vigor born from snowmelt high in the Absaroka and Beartooth ranges. The banks rose steeply in places, adorned with towering sandstone rimrocks--layers of sediment deposited during the Cretaceous period, roughly 70 to 80 million years ago. These cliffs, etched and sculpted by wind and water, displayed strata that spoke of ancient seas and shifting landscapes long vanished beneath the relentless march of geological time.

Clark’s journals reveal both a practical mind and an artist’s eye for the natural world. He noted the river’s “swift and clear” current, a lifeblood threading through the rugged terrain. Along the way, he named several landmarks, including one that he recorded with lasting intention: Pompey’s Pillar. This remarkable sandstone butte rises approximately 150 feet above the river, its vertical face a natural monument shaped by erosion and time. On July 25, Clark carved his name and the date--“William Clark July 25, 1806”--into the soft sandstone, leaving the only physical inscription from the expedition still visible today.

That inscription offers a direct voice from the past, a human signature amid the ancient rocks. Clark’s words, etched with a knife, declared presence and passage: “I am here,” if only for a moment. It is a reminder that while the landscape endures through epochs, human endeavor imprints itself briefly but indelibly.

The flora and fauna encountered by the expedition also merit attention. Along the riverbanks, groves of Populus deltoides, commonly known as eastern cottonwood, provided the raw material for their canoes. The undergrowth included chokecherry (Prunus virginiana) and wild rose (Rosa woodsii), their blossoms a subtle fragrance carried on the warm July breezes. Fauna sightings recorded by Clark and his men ranged from soaring raptors--bald eagles (Haliaeetus leucocephalus) and golden eagles (Aquila chrysaetos)--to herds of bison (Bison bison), whose massive forms grazed the adjacent plains.

Clark’s writings also reflect an acute awareness of the land’s geological complexity. He observed the “high cliffs of red and yellow sandstone” lining the river, formations that modern geologists identify as part of the Hell Creek Formation and other Cretaceous sedimentary units. These layers hold fossils of ancient reptiles and plants, vestiges of a world vastly different from the one Clark and his companions navigated.

The Daughters of the American Revolution, Shining Mountain Chapter, recognized the significance of this locale and its connection to the expedition’s history. In 1924, they erected a marker near the riverbank to commemorate the centennial of Clark’s passage. The inscription is succinct, yet powerful: “Captain Clark, of the Lewis and Clark Expedition, passed down the river opposite this point July 24, 1806.” This marker anchors a moment in time, inviting reflection on the intersection of human exploration and the enduring natural world.

One cannot help but consider Clark’s voyage in light of the vastness and endurance of the Yellowstone River itself. Flowing some 692 miles from its headwaters in the Absaroka Mountains to its confluence with the Missouri near Buford, North Dakota, the Yellowstone drains a watershed of approximately 70,000 square miles. Its course carves through geological layers that represent over 100 million years of Earth’s history, shaped by volcanic activity from the Yellowstone hotspot and sculpted by glaciers during the Pleistocene epoch.

Clark’s journey down this river was more than a route home; it was a passage through deep time and varied ecosystems. The river’s channel, braided in places and confined in others by steep canyon walls, reflects the dynamic interplay of sediment transport, water flow, and tectonic uplift. As Clark and his party floated downstream, they moved through environments ranging from montane forests dominated by Pseudotsuga menziesii (Douglas fir) and Pinus contorta (lodgepole pine) to open grasslands where Artemisia tridentata (big sagebrush) stretched across the plains.

In the words of William Clark himself, recorded in his journal on July 24, 1806: “The river is clear and the current swift. The cliffs here are high red sandstone and rise precipitously from the water’s edge, forming a passage of great grandeur and commanding views.” This passage, carved through layers of red and yellow sandstone, remains a remarkable corridor where natural history and human history intersect.

Today, visitors to Billings may stand near the riverbank and imagine the expedition’s canoes gliding past, propelled by strong arms and keen eyes. They may look up at Pompey’s Pillar, where Clark’s inscription endures--a tangible link to a journey that shaped the course of American history. The Yellowstone River continues its relentless flow, indifferent to the names and dates humans leave behind, yet ever inviting those who seek to understand the land’s past and the stories etched within its stones.

See also

• Lewis and Clark Yellowstone River Journey at Billings, Yellowstone County
• Lewis and Clark Expedition July 24, 1806 at Laurel, Yellowstone County