The Oregon Trail: Four Hundred Thousand People Through Wyoming

Stand on the rock at Independence Rock and you are standing on the most important landmark in two thousand miles. Emigrants called it the Great Register of the Desert. From the eighteen forties through the eighteen sixties, every wagon company heading west measured its progress by whether it reached Independence Rock before the Fourth of July. Arrive by Independence Day, and the math said you would clear the Sierra Nevada before the first autumn snow. Arrive later, and you gambled.

The rock itself is a granite dome rising a hundred thirty feet from the Sweetwater River plain. Tens of thousands of emigrants carved or painted their names on its surface. Many of those inscriptions survive. You can read them today.

Between approximately eighteen forty-one and eighteen sixty-nine, somewhere between three hundred fifty thousand and five hundred thousand people walked or rode across Wyoming on the Oregon, Mormon, California, and Pony Express trails, which shared a common route through much of the territory. This is more people than currently live in Wyoming. They crossed South Pass, the broad saddle in the Wind River Range where the Continental Divide drops to seventy-five hundred feet, low enough for wagons. The ruts their wheels cut into the sandstone ledges at Guernsey are four to six feet deep in places, still visible today. NASA imagery shows the trail's passage across South Pass from orbit.

The last major wagon season was eighteen sixty-nine. The transcontinental railroad, completed that same year at Promontory Summit in Utah, made the journey in days instead of months. The trail was abandoned almost immediately.

For the Lakota, Eastern Shoshone, Northern Arapaho, and Northern Cheyenne nations whose territory the emigrants crossed, the trail was not an adventure. It was four hundred thousand strangers a year moving through their homelands.