“Children’s playground on roof of large New York [City] store while mothers are shopping,” ca. 1919, by Bain News Service, via Library of Congress Prints and Photographs Division (both photos).
There’s a good article on early 20th century New York City roof gardens here.
Cake shop and café in Halmstad, Halland, Sweden, between 1920 and 1939, by Otto Nilsson, via Swedish National Heritage Board Commons on flickr.
You can click on the photo to enlarge it.
Placing potted bay trees on the east wing terrace, White House, Washington, D.C., between 1910 and 1917, by Harris & Ewing, via Library of Congress Prints and Photographs Division (both photos).
East terrace, White House, 1923, by National Photo Company.
Also from France, by Eugène Trutat . . .
“Portrait de famille sur une terrasse,” 1901, via Bibliothèque de Toulouse Commons on flickr.
San Giorgio cloister, Verona, Italy, May 19, 1878, via National Archives of Estonia Commons on flickr.
The watercolor is one of many Italian scenes collected (perhaps painted?) by a Baroness Meyendorff in the 1870s and early 1880s.