On September 16, 1776, a small expedition forded the Green River near this spot and named it the San Buenaventura, or river of good fortune. Led by Atanasio Dominguez and Silvestre Velez de Escalante, two Franciscan friars seeking a northern route from Santa Fe, New Mexico, to newly established Spanish missions in Monterrey, California, the party became the first known group of Europeans to enter what is now Dinosaur National Monument. Their maps and journal entries recorded many of the area's prominent landmarks, including the surrounding mountains and hills. The friars eventually explored Utah Valley, south of modern day Salt Lake City, then abandoned their effort to reach California and endured a difficult return to Santa Fe through the canyon country around the Colorado River in what is now Southern Utah. Although they failed in their stated goal, the Dominguez-Escalante Expedition is credited as the first group to map vast areas of the American West, paving the way for later travelers and setting in motion dramatic changes for the native peoples who inhabited the area.