Macomb's San Juan Exploring Expedition (1859)

Macomb’s San Juan Exploring Expedition led by Captain John N. Macomb, had military and political origins. Its primary purposes were to locate a route for the movement of military supplies from Santa Fé, New Mexico to Utah, and to map unknown portions of the geography in the western United States. Despite these missions, as the explorers traveled the Old Spanish Trail, collectors like Botanist John S. Newberry had ample time to study the environment. While continuing travels along the San Juan River, rainy weather proved a challenged for preserving the zoological and botanical specimens collected. The party continued on and explored the mountains and tributaries of the San Juan River and the Rio Navajo tributary. Newberry took a side trip to find the junction of the Grand and Green Rivers.