Fine large format map of south central Colorado and part of New Mexico, as surveyed in 1874 by the Hayden Survey.
The map is centered on the Alamosa / Fort Garland area and extends to Trinidad, Colorado, and the headwaters of the Canadian River in the southeast, to the Colorado City area in the northeast, and the San Luis Peak / Wagon Wheel Gap area in the northwest, as well as the area around Pagosa Springs and Dulce in southwest Colorado and Northern New Mexico.
Hayden organized and led previous expeditions into the Rocky Mountains, both before and after the Civil War. In 1869, he led an expedition along the Front Range to Denver and Sante Fe. In 1870 he received a $25,000 governmental grant to lead a 20-man expedition to South Pass, Fort Bridger, Henry's Fork, and back to Cheyenne.
In 1871, Hayden led a geological survey into the Yellowstone region of northwestern Wyoming. The survey consisted of some 50 men which included notables such as Thomas Moran, and painter and famous frontier/Civil War photographer William Henry Jackson. The following year Hayden and his work, Preliminary Report of the United States Geological Survey of Montana and Portions of Adjacent Territories; Being a Fifth Annual Report of Progress was instrumental in convincing Congress to establish Yellowstone as the first U.S. National Park, aided by Jackson's stunning large-format photographs and Moran's dramatic paintings. These publications also encouraged the westward expansion of the United States
From his twelve years of labor and annual survey journeys there resulted a most valuable series of volumes in all branches of natural history and economic science; and he issued in 1877, his Geological and Geographical Atlas of Colorado. The last of the annual survey journeys was in 1878. As a result of Hayden's extensive geological work, he uncovered numerous dinosaur fossils which he brought back east with him for further scientific study. Much of what he brought back is still housed in the collection of the Smithsonian Institution.