The Historic American Buildings Survey (HABS) and the Historic American Engineering Record (HAER) collections are among the largest and most heavily used in the Prints and Photographs Division of the Library of Congress. Since 2000, documentation from the Historic American Landscapes Survey (HALS) has been added to the holdings. The collections document achievements in architecture, engineering, and landscape design in the United States and its territories through a comprehensive range of building types, engineering technologies, and landscapes, including examples as diverse as the Pueblo of Acoma, houses, windmills, one-room schools, the Golden Gate Bridge, and buildings designed by Frank Lloyd Wright. 

Administered since 1933 through cooperative agreements with the National Park Service, the Library of Congress, and the private sector, ongoing programs of the National Park Service have recorded America's built environment in multiformat surveys comprising more than 581,000 measured drawings, large-format photographs, and written histories for more than 43,000 historic structures and sites datingafrom Pre-Columbian times to the twentieth century. This online presentation of the HABS/HAER/HALS collections includes digitized images of measured drawings, black-and-white photographs, color transparencies, photo captions, written history pages, and supplemental materials. Since the National Park Service's HABS, HAER and HALS programs create new documentation each year, documentation will continue to be added to the collections. The first phase of digitization of the Historic American Engineering Record collection was made possible by the generous support of the Shell Oil Company Foundation.

https://www.loc.gov/pictures/collection/hh/