The Continental Divide at Lemhi Pass: Where Lewis and Clark Ran Out of Continent

Meriwether Lewis reached the crest of the Continental Divide at Lemhi Pass on August twelve of eighteen oh five. He had been traveling for more than a year since leaving Camp Dubois in Illinois. He walked up the final slope expecting to see, on the other side, the upper waters of the Columbia River system and a short portage to the Pacific.

What he saw instead was more mountains. Range upon range extending to the horizon, with no indication of a navigable route through them. Lewis wrote in his journal that the view was immense, and that the river descending from the pass was not the broad, navigable Columbia he had hoped for. The Pacific was still more than a thousand miles away.

Lemhi Pass sits at seven thousand three hundred seventy-three feet on the Montana-Idaho border, within the Beaverhead-Deerlodge National Forest on the Montana side and the Salmon-Challis National Forest on the Idaho side. It is accessible via a gravel road that becomes impassable in winter and marginal in wet weather.

The Shoshone people, led by Chief Cameahwait, were encamped in the valley on the Idaho side. Sacagawea recognized Cameahwait as her brother, a reunion that is documented in both Lewis and Clark's journals. The Shoshone provided horses that made the mountain crossing possible.

The pass is now a National Historic Landmark. The undeveloped character of the surrounding terrain means the view Lewis saw in eighteen oh five is substantially unchanged, except that the mountains he was looking at have fewer trees than they did then.