Landscape Architecture Resources

 The Library of Congress
Gateway to rich primary source materials relating to the history and culture of the United States.
The site offers more than 5 million items from more than 90 historical collections - including these selected image collections:

• Architecture, Engineering and Landscapes ~ HABS/HAER/HALS ~ Multiformat ~ 1913-Present: Built in America: Historic American Buildings Survey/Historic American Engineering Record/Historic American Landscapes Survey, 1933-Present
• Environment, Natural ~ Photographs ~ 1891-1936: American Environmental Photographs, 1891-1936: Images from the Chicago Library
• Folk Culture and Natural Environment, West Virginia ~ Multiformat ~ 1992-1999: Tending the Commons: Folklife and Landscape in Southern West Virginia
• Landscape and Architectural Design ~ Multiformat ~ 1850-1920: American Landscape and Architectural Design, 1850-1920: A Study Collection from the Harvard Graduate School of Design
• National Parks ~ Maps: Mapping the National Parks
• Panaromic Maps ~ 1847-1929

Sample Library of Congress keyword search: 

• Tempe canals
• Desert landscape
• Farm Landscape
• Landscape photographs

 ARTstor Digital Library

The ARTstor Digital Library is comprised of digital images and related data and the tools to make active use of those images. The Collection contains approximately one million digital images of visual material from different cultures and disciplines.

The collection documents artistic traditions across many times and cultures and embraces  such topical areas as: architecture, garden and landscape, decorative arts, painting, sculpture, photography, and design -- as well as many other forms of visual culture.
ARTstor contains the following topical collections:

• Beyond the Taj: Architectural Traditions and Landscape Experience in South Asia: Architecture, pilgrimage sites, cultural traditions, and rituals in South Asia
• Foundation for Landscape Studies: Photographs of landscapes, gardens, and parks around the world, as well as historical illustrations of gardens

Additionally, ARTstor has images of some of the work by such land/environmental artists such as: Andy Goldsworthy, James Turrell, Beverly Pepper, Nancy Holt, Robert Smithson, Michael Heizer, Alan Sonfist, et al. 

Calisphere

Open access image and primary source database, provided by the University of California. Includes historic images of California landscapes, maps, and gardens. 

Digital Sanborn Maps, 1867-1970 (Arizona)

Provides digital access to historic maps of towns and cities in Arizona.