I-76, and US 6 in the previous Part and the beginning of this one (from Fort Morgan north to Sterling), are the inheritors of this leg of the Overland Trail and the corresponding Overland Stage Line. In this region the Trail mostly follows the course of the South Platte River, which wends from its headwaters southwest of Denver up to Greeley and thence to Fort Morgan and Sterling before entering Nebraska, near Julesburg, CO and Big Springs, NE. From there it continues south of Ogallala to the North Platte River for a total distance of 439 miles, and the combined Platte continues on as a tributary of the Missouri River and the great Mississippi River (which we will reach in a couple more states).

The geographic advantage of the South Platte's course was not initially realized in 1857 when the US Post Office solicited bids for mail service along what was then called "the southern route." This contract covered service from Memphis, TN to San Francisco using a convoluted but all-weather route via New Mexico and Arizona, and was operated by the Butterfield Overland Mail Company until the Civil War broke out in 1861 and transected it. (We talk about the old Butterfield Trail in Old Highway 395 Part 10.)

This left the Union with a problem. George Chorpenning's northern route was defunct, problematic because of its latitude and generally slower operations which had led to his contract's annulment in 1860. The subsequent Pony Express, which followed the Oregon Trail and Mormon Trails to Salt Lake City and thence to Sacramento, was too expensive to replace it and faded by 1861 as well. Furthermore, the need for soldiers had depopulated many of the western forts along those trails of regular Army and left less well-trained volunteers in place, whose inexperience hostile Indian raiders readily exploited. If mail service was to be restored, a new route would need to be found.

Fortunately, an alternative routing was known to local traders from as early as 1825 from the Laramie Plains to the North Platte, part of which is on the roadbed we travel now. Combined with the Cherokee Trail and other local discoveries, the new Overland Trail and Overland Stage Route was opened on July 1, 1861. It proceeded west from Atchison, KS to ascend the South Platte to Greeley, CO and then partially along the course of the 1854 Cherokee Trail through Wyoming to Fort Bridger, where it met the Oregon, California and Mormon Trails for points west. For a time the new Trail became the most heavily traveled road in the country. Ben Holladay, who had purchased the assets of the Pony Express' parent company and retained the contract, operated stage service until 1866 when it was sold to Wells Fargo, who operated it in turn until 1869 when the transcontinental railroad made its services obsolete.