Lunch Atop A Skyscraper (1932) – Charles C. Ebbets
Although really dangerous to pull off, this shot, called Lunch Atop A Skyscraper, was actually part of a promotional campaign. Taken on the 69th floor of the Rockefeller Center, the image became a symbol of New York Unity and has also become widely distributed.
As a matter of fact, former Manchester United manager Sir Alex Ferguson used to have a large one on his wall. He would often use it to instill team ethic into young players joining the team. He would tell them that the photo shows teamwork, a group of men sticking together and prepared to sacrifice themselves if one should slip and fall.