Francisco Atanasio Domínguez

The Dominguez–Escalante expedition was conducted by a Spanish party in 1776 to find an overland route from Santa Fe, New Mexico to their Catholic mission in Monterey, northern California. Atanasio Domínguez and Silvestre Vélez de Escalante, Franciscan priests, and Bernardo Miera y Pacheco, acting as the expedition's cartographer, traveled with eight men from Santa Fe through present-day western Colorado to the Utah Valley (in the state of present-day Utah). Along part of the journey, they were aided by three Timpanogos (Shoshone or Ute people) guides.

Due to hardships during travel, the group did not reach Las Californias, but returned to Santa Fe through Arizona. The maps and documentation of their expedition aided future travelers. Their route became part of the Old Spanish Trail, a trade route from Santa Fe to Pacific Coast settlements.

The Dominguez–Escalante Expedition (more correctly called the Dominguez-Vélez expedition) was conducted in 1776 to find a route from Santa Fe, New Mexico, to Spanish missions in California, such as the Spanish presidio at Monterey in Las Californias. On July 29, 1776, Atanasio Domínguez led the expedition from Santa Fe with fellow friar Silvestre Vélez de Escalante and cartographer Bernardo de Miera y Pacheco (Miera). The initial part of their journey followed the route taken by Juan Rivera eleven years earlier into Ute country of southwestern Colorado. Three Timpanogo guides led them through Colorado and Utah.

These Spanish were the first European men to travel the route through much of the Colorado Plateau into Utah, and back through Arizona to New Mexico. During the course of their trip, they documented the route and provided detailed information about the "lush, mountainous land filled with game and timber, strange ruins of stone cities and villages, and rivers showing signs of precious metals."

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