Air conditioners, more than 500 in total, hang on the wall of an office building on August 15, 2011 in Fuzhou, Fujiang Province of China. This 25-story office building was built with no central air conditioner system, each office has it own individual unit installed on the exterior creating this wall of air conditioners. (Photo by ChinaFotoPress/Getty Images)

“The Eton wall game is a game similar to football and Rugby Union, that originated from and is still played at Eton College. It is played on a strip of ground 5 metres wide and 110 metres long next to a slightly curved brick wall, erected in 1717”. – Wikipedia

Photo: The “Collegers” and the “Oppidans” of Eton College take part in the “Wall Game” as boys in their traditional school uniform watch from on top of the wall on November 17, 2007 in Eton, near Windsor, Berkshire, England. The first recorded “Wall Game” took place in 1766 with competition between the two houses at the boarding school remaining as fierce as ever on the annual St. Andrew's day event. The object of the game is to get the ball to either end of the wall and score a goal, which has not happened since 1909. As well as scoring a goal the players can win points with a “shy”, where the ball is held against the wall and touched by the hand and awarded one point. (Photo by Christopher Furlong/Getty Images)

Portuguese runner Adriele Silva gestures during the Great Wall Marathon at the Huangyaguan section of the Great Wall of China, in Jixian of Tianjin, China May 19, 2018. (Photo by Jason Lee/Reuters)

Ten segments of the Berlin Wall, which constitute the longest stretch outside of Berlin, are seen on display in Los Angeles, California September 18, 2014. On November 9, Germany will celebrate the 25th anniversary of the fall of the Berlin Wall. To mark the event Reuters Photographers around the world captured images of segments of the wall, which are kept as monuments in many countries from Taiwan to South Africa and Costa Rica. (Photo by Mario Anzuoni/Reuters)

Tourists from Holland peak through a crack in a still-existing portion of the Berlin Wall at the main memorial to the Wall in Bernauer Strasse on the 22nd anniversary of the fall of the Wall on November 9, 2011 in Berlin, Germany. The Berlin Wall, erected by the communist authorities of then East Germany in 1961, divided the city and prevented East Germans from travelling west until the collapse of the Eastern Bloc in 1989. (Photo by Sean Gallup/Getty Images)

Climbers ascend the walls of the Westway Climbing Centre on June 15, 2011 in London, England. The Westway indoor climbing centre is located under the A40 flyover in Shepherd's Bush has over 350 climbing routes, some of which rise to over 14 meters. (Photo by Oli Scarff/Getty Images)

A two-horse team street cleaner, with sprayer, squeegee, and roller at rear. New York, between ca. 1910 and ca. 1915. (Photo by NYC Municipal Archives)

Documentary photographer William E. Crawford was one of the first Western photographers to gain access to North Vietnam after the war ended. He has photographed the capital, Hanoi, at regular intervals since 1985, concentrating on the colonial and indigenous architecture, urban details, landscapes and intimate portraits of people in their home settings, street scenes and the city’s surrounding countryside. Here: 54 Hàng Ga (Chicken Street), 1994. (Photo by William E. Crawford from the book “Hanoi Streets 1985-2015: In the Years of Forgetting”)