"Bison once moved across North America in herds that blackened the landscape in all directions, in numbers estimated not in the hundreds but in the tens of thousands.
"These last animals are now so numerous that from an eminence we discovered more than we had ever seen before at one time; and if it be not impossible to calculate the moving multitude, which darkened the whole Plains, we are convinced that twenty thousand would be no exaggerated number,” Lewis and Clark remarked during their cross-country journey in 1805-06 of a herd encountered near the White River in present-day South Dakota.
It's been estimated that prior to American colonization there were tens of million of bison roaming North America, perhaps as many as 60 million. They traveled in huge herds that challenged present-day imagination. So great were bison numbers, and so faithful were they to their migratory routes, that countless years of millions of trampling hooves had carved “traces” as much as 50 feet wide across the landscape, paths that humans later turned into roads.
Lewis and Clark, George Rogers Clark, and even Abraham Lincoln walked the “Buffalo trace” that runs between present-day Louisville, Kentucky, and Vincennes, Indiana.
Richard Irving Dodge, a Civil War veteran transformed into a frontiersman for the U.S. Army, recalled standing atop a sandstone outcrop in Kansas that offered him views covering 6 to 10 miles in every direction."
Kurt Repanshek reports for National Parks Traveler August 28, 2025.
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