On 29 July 1776, Franciscan friars Francisco Atanasio Dominguez and Silvestro Velez de Escalante embarked on an expedition to seek an overland route from Santa Fe, New Mexico to Monterey, California. Although the Spaniards did not reach their final destination, the expedition is widely regarded as one of the great explorations in western U.S. history for its documentation of the land and Native peoples in the Four Corners. The group -- including cartographer Don Bernardo Miera y Pacheco, Ute-speaking guides and the alcade (mayor) of Zuni -- circumnavigated 1800 miles of unchartered territory never before seen by Europeans, an arduous five month trip documented in Escalante's journal, a widely read historical account of the exploration. More than two hundred years later Greg Mac Gregor and Siegfried Halus have created a remarkable visual record of the expedition. Using Escalan-te's journal as their guide, the photographers followed the expeditionary route, circling through New Mexico, Colorado, Utah, and Arizona, and documenting the frontier as first witnessed by the Spanish explorers on horseback. The expedition passed what today are major national parks and landforms: Zion Canyon; Dinosaur Monument; and the Grand Canyon. The photographs show many areas virtually unchanged over centuries; other images reveal the passage of time in pictures of dammed rivers, power lines, and towns where once stood virgin forests. Quoting widely from Escalante's journal, the authors present first hand accounts of the expedition alongside their photographic narrative. Essays by the photographers discuss their methodology and experiences as modern day explorers retracing the steps of the friars. In his historical essay, Joseph P Sanchez writes about the lasting legacy of the Spanish expeditions.