The natural landscape is perhaps one of the most widely photographed subjects, from fine art to journalism, and some of its leading practitioners, such as the American photographer Ansel Adams, have become cultural icons. Historically, landscape photography’s rise coincides with the period of American westward expansion during the late 19th century, when photographers joined government survey teams and railroad companies to document the vast expanse of nature before them. In contrast to today’s conditions, these intrepid documentarians carried heavy equipment and transportable darkrooms to process photographs on site. Notable examples include Carleton E. Watkins, whose mammoth-plate photographs of Yosemite Valley were influential in the government’s decision to initiate the National Park System, and Ansel Adams, whose breathtaking black-and-white photographs took part in a tradition of environmental advocacy. In the 1970s, the New Topographics movement challenged Adams’s immaculate view of nature by turning an eye toward encroaching industrialization and tourism, a critical approach that many artists—from the Düsseldorf School photographers to Trevor Paglen—continue today.