Built in 1928, the Greenhorn Creek Bridge carried Pueblo County Road 273/Apache City Road over Greenhorn Creek and was a rare example of a Warren deck truss structure. Its association with the early route known as the Great North-South Highway and the infrequent use of that structural type led to its eligibility for the National Register of Historic Places in 2000. While the Colorado Highway Department constructed many rigid-connected trusses in the 1920s and 1930s, most were pony or through truss structures with the road deck at the base of the truss superstructure, and this bridge differed by placing the truss below the deck. The Great North-South Highway, one of the state's original automobile routes and known as US Highway 85 after 1926, grew from early wagon and stagecoach lines. The area around Greenhorn Creek had long been visited by trappers and travelers, and small communities such as Greenhorn and Apache City developed along the route in the mid-to-late 1800's. By 1949, this stretch of the highway had been rerouted to the east, and the construction of Interstate 25 in the 1950s and 1960s drew most travelers away from the old road. In the early 1960s, the route was conveyed to Pueblo County and was no longer paved, and travel over the 1928 bridge on the relatively unimproved county road recalled the era of early automobile travel in Colorado. The bridge was replaced in 2019.