The Esposizione universale was a planned World's Fair that was intended to be held in Rome in 1942. The fair was intended to celebrate twenty years of Italian fascism under Benito Mussolini. Although extensive preparations were made under Italy's Fascist government, the exhibition was cancelled on 3 June 1940, following the entry of Italy into World War II in 1940. A substantial area of Rome named the Esposizione Universale Roma, also known as E42 or EUR, was developed in preparation for the fair. Although never inaugurated, the E42 project remains a significant example of Fascist architecture and urban planning.