Conceived in 1911 to attract automobile tourists, the dirt-surfaced Rainbow Route ran from Pueblo to Montrose along old stagecoach roads and railroad grades, and its twenty-two mile stretch through Bighorn Sheep Canyon east of here was among the hardest to build, with convict laborers from the state penitentiary in Canyon City cutting through hard-rock cliffs by hand and hauling away rubble one wheelbarrow load at a time; that segment opened in 1915, though travelers often needed ropes and shovels to get through, the road reached the Continental Divide at 11,386-foot Old Monarch Pass six years later, and by the 1950s most of it had been incorporated into U.S. 50. The Utes, Colorado's oldest inhabitants, had lived here for at least a thousand years and were found in possession of the Central Rockies by the earliest Spanish explorers in the seventeenth century; after becoming one of the first tribes to acquire horses, they expanded their territory from the Utah deserts to the plains of eastern Colorado by the early eighteenth century and held off intruders until the late 1800s, when gold and silver seekers reduced their vast domain to two small reservations in Colorado and one in Utah. In western Fremont County, cattle ranchers became some of the earliest full-time settlers beginning as early as 1870, raising hay and livestock along the Arkansas River, driving herds into South Park, and often operating ranches that also served as hotels, stagecoach stops, general stores, and hospitals; nearby mining towns and, after 1880, railroad service created strong markets for beef, and despite dangers such as blizzards, droughts, predators, cattle thieves, and collapsing prices, ranching endured as Fremont County's backbone. In April 1882, sixty-three Russian Jews driven from their homes by tsarist oppression arrived at Cotopaxi under a plan by mine magnate Emanuel Saltiel, who promised each family a house, farmland, and supplies, but they found only twelve tiny shacks and distant, rocky, poorly watered land; after a disastrous harvest many worked for Saltiel, later found jobs with the Denver & Rio Grande Railroad, and were aided through the winter by neighbors, and although another failed crop ended the colony, most of the twenty-two original families remained in Colorado and helped found Jewish communities across the state.