Aerial photographs from 1922 juxtaposed with 1919 maps
The comparison above is (on the left) a mosaic constructed from 215 photos taken from an altitude of 10,000 feet. To capture these images, the U.S. Army Air Service spent more than two hours circling the area taking from a plane traveling about 100 miles an hour. The map on the right is a 1919 Baist's real estate atlas of surveys of Washington. See originals at the Library of Congress: 1922 DC aerial view | Baist book of DC map surveys.
Baist's Real Estate Atlas of Surveys
List will be updated in coming months.