The geography involved in describing the trail drive is absurd. First of all, there weren’t roads to follow in going from Abeline, KS to the Big Horn area of Wyoming, rather they would be moving over open range following trails at best. Secondly, the route would stay in open range miles and miles east of the foothills in Colorado. A drive through the foothills would take much, much longer than one going through the high plains, and a good portion of the herd wouldn’t even make it through that terrain. It’s doubtful that aspen trees would be anywhere near a cattle drive trail in the plains. I live on the edge of the Front Range foothills and know firsthand that it’s just not trail country. Ranching up there at the time was for local use only until some railroads made livestock transport practical some tears after the mid-1870s.