The paper analyzes the reasons that made Milan the “City of Fairs” for over a century. The hypothesis is that the city has been able to interpret and disseminate the cultural paradigms linked to the idea of development that have led the growth of the city itself and the entire country. It deals primarily with the cultural factors underlying the creation of large international exhibitions, starting with the London Fair in1951 and the Paris Fair in 1889, showing their presence in the International Fair of Milan in 1906. Particularly strong are the aspects linked to nationalistic affirmation, faith in science and work, and the use of new forms of spectacle. The essay then analyzes the fracture caused by World War II and the many changes following it, both regarding the places of fairs and the underlying cultural messages. It emerges a new awareness about the role of consumption and, over time, different forms of spectacle trying to adapt to the new media. In this context also the Milan Fair in 2015 seems to be fully representative of the actual cultural change.