Nearly 4,000 panoramic photographs of cityscapes, landscapes, and group portraits, deposited as copyright submissions by more than 400 companies, are displayed on this site. Panoramic photographs were used to advertise real estate and to document groups, events, and gatherings. Images depict all 50 states, the District of Columbia, and more than 20 foreign countries and territories. Subjects include cityscapes, landscapes, group portraits, agricultural life, disasters, education, engineering, fairs and expositions, industrial scenes, military activities, performing arts, sports, and transportation. Although the images cover the period from 1851 to 1991, the collection centers on the early 20th century. The site includes a bibliography, an illustrated 1,000-word background essay on the history of panoramic photography, and an essay outlining the technicality of shooting a panoramic photograph. Four essays focus on specific photographers: George R. Lawrence (1869–1938); George N. Barnard (1819–1902); Frederick W. Brehm (1871–1950); and Miles F. Weaver (1879–1932).