U.S. International Transportation Exposition, better known as Transpo '72, was a trade show held on 300 acres (1.2 km2) of land at Dulles International Airport outside Washington, D.C. for nine days from May 27 to June 4, 1972. The $10 million event, sponsored by the U.S. Department of Transportation, was a showcase for all sorts of transportation-related technologies. Over a million visitors flocked to the show from all over the world. According to the Wall Street Journal, it was "the biggest show the government has put on since World War II."
Transpo hosted the world's largest air show, all of the new widebody airliners, high-speed trains and demonstrations of the latest automated guideway transit systems. In addition to featuring futuristic technology "Flying trains, square dancing helicopters and the fantasy of a wonderland," according to a news release, Transpo '72 covered all current modes of transportation as well. General Manager William J. Bird explained, "We want to emphasize totally integrated systems in our future transportation..."
The event was officially opened by the second U.S. Secretary of Transportation, John A. Volpe.
Transpo was the idea of L. Mendel Rivers, chairman of the House Armed Services Committee. Rivers had visited the Paris Air Show on occasion; at the time, there were a "ring" of three major air shows in Europe that took turns hosting, Farnborough, Paris and Hanover. Visitors from around the world could come to the show where sales teams from the aviation firms were ready to sign deals for their latest products. Rivers lamented the fact that there was no similar industry-based show in the U.S. Rivers started planning a U.S. version of the air/trade show, and selected Washington as a natural location due to the density of military contacts and the presence of the recently expanded Dulles Airport. Rivers went to Congress with a request for $750,000 in funding.