Lewis and Clark Pass, near Lincoln, Montana
Late in the day on 7 July 1806, Lewis and his party crossed "the dividing ridge between the waters of the Columbia and Missouri rivers" at today's Lewis and Clark Pass to the headwaters of the Dearborn River. Lewis said little about the area other than that he could see the landmark now called Square Butte—faintly discernable in the photo, just right of center on the horizon—which the Corps had dubbed Fort Mountain the previous July. In the small clearing at right of center in the photo, traces of travois poles dragged across the divide by generations of Indians remain to this day faintly etched in the shallow, rocky mountain soil.
Lewis and Clark Pass—which, of course, Clark never saw—is six miles north of Rogers Pass, where Montana Highway 200 crosses the Continental Divide. The concept of the continental divide, and the term itself, would emerge only after another fifty years of western exploration. However, the map Clark prepared for the first edition of his and Lewis's journals, which appeared in 1814, would be the first to show with reasonable accuracy the mountains separating two of the largest continental watersheds, the Columbia and the Missouri, at this point in the Northern Rockies.
From Discovering Lewis & Clark from the Air
Photography by Jim Wark
Text by Joseph Mussulman
Reproduced by permission of Mountain Press