As they passed through Paiute country in Utah and Nevada, some traders victimized the Indians by taking slaves to add to their stock of trade goods. Women and children were in demand as slaves both in California and New Mexico.
Occasional travelers followed the trail to California, among them American trappers, entrepreneurs, and government agents, as well as settlers from New Mexico. Mounted Indians were commonly seen along the eastern sections of the trail.
The Spanish Trail consisted of a 1,120-mile northward-looping course traversing six states--New Mexico, Colorado, Utah, Arizona, Nevada, and California. Hostile Indian tribes--Apaches, Navajos, and Mojaves--prevented the opening of a direct route between Santa Fe and Los Angeles. To circumvent the great canyons of the Colorado River system, the trail was pushed northward to the open country at Green River, Utah.
The word "Spanish" is something of a misnomer since the trail was in use only during the time when the region traversed was part of Mexico. The term comes down to us in the writings of American explorers who, as they traveled along sections of the trail, concluded that it had been opened by Spain. Thus it appears in their diaries and maps as the "Spanish Trail." John C. Frémont was one of those who used the name. After 1848, when sovereignty of the region passed to the United States, American travelers in some numbers described the "Old" Spanish Trail, and their writings provide clues for anyone seeking its location.
The trail was simply that--a trail; it was not used by wheeled vehicles until 1848 when the Mormons developed the western section for wagon travel between Salt Lake City and southern California. It was the first extensively used route to cross the region now within the boundaries of Utah. The Utah sector, the longest of any within the trail states, was 460 miles. Recently completed field research has revealed the actual location of the trail throughout its course from Santa Fe to Los Angeles.
The Spanish Trail literally began northwest of Santa Fe at Abiquiu, the last European settlement during the trail days; between New Mexico and the frontier outpost of Cucamonga in California was a distance of about a thousand miles. In Colorado, the trail passed through or near Ignacio, Durango, Dolores, and Dove Creek. It crossed into Utah near the tiny settlement of Ucolo, about fifteen miles east of Monticello.
In order to head the great canyons of the Colorado and Green rivers, the Spanish Trail held to a northwest course as far as the present town of Green River. From Green River, the trail crossed the northern part of the San Rafael Swell, missing its rugged interior. From here, the trail carried early travelers on an easy course along the wide, well-watered floor of Castle Valley, and then crossed the Wasatch Plateau to continue through the Great Basin, via Sevier River Valley, the Markagunt Plateau, the Parowan Valley, and the Escalante Desert. On the southern edge of the Escalante Desert, the trail passed up Holt Canyon to Mountain Meadows, a favorite resting place, known in the trail days as "Las Vegas de Santa Clara." Leaving the meadows, the trail turned down the tributaries of Magotsu Creek and Moody Wash to the main Santa Clara River, through the homeland of the Southern Paiute Indians.
At a point where the Santa Clara River makes a bend to the east, the Spanish Trail left the river and climbed over the Beaver Dam Mountains, following a course practically identical with that of old U.S. Highway 91. On the west side of the Beaver Dam Mountains, on Utah Hill, the trail entered a forest of Joshua trees marking the eastern limits of the Mohave Desert. The Spanish Trail then left Utah, cut across the northwest corner of Arizona, and traversed southern Nevada, following the Virgin River for some distance. The good springs at Las Vegas stopped every caravan. The trail then crossed the Mohave Desert to southern California. Threading Cajon Pass, caravans reached San Gabriel and, finally, Los Angeles, at the end of the trail.