From the late 1830s into the 1860s, thousands of traders, emigrants, and gold prospectors passed this way after crossing the Big Blue River, where covered wagons struggled up the hill through mud left by torrential spring downpours. Over the years, countless wagon wheels and hooves churned the earth and rain washed away the loose soil, creating the swales here. Freight wagons bound for Santa Fe carried trade goods such as bolts of fabric and boxes of tools and cookware, and on return trips traders might haul wool, mules, coins, silver bars, or gold dust as payment. Emigrants and gold prospectors also traveled this route toward Oregon or California in wagons pulled by oxen or mules and loaded with enough food and necessities for several months. The Oregon and California trails served fur traders, gold seekers, missionaries, and emigrants, and from 1841 to 1861 more than 300,000 emigrants followed this route from the Midwest to Oregon farmlands or California gold fields on journeys lasting five months. From 1821 to 1846, the Santa Fe Trail was an international road for American and Mexican traders, and after the Mexican-American War ended in 1848 and the United States gained much of the present-day American Southwest, it became a national road for commercial and military freighting, stagecoach travel, emigration, and mail service.
