International Exposition Center, Ohio

The International Exposition Center claims to have 2.2 million square feet, making it one of the largest single-building trade show exhibition buildings in the country. It was once known as part of Air Force Plant 7, established at what is now Cleveland’s international airport. In WWII, the Cleveland Bomber Plant was built there, operated by General Motors, building B-29 bombers. On the other side of the runways the Aircraft Engine Research Laboratory was built. After the war, the airport became a municipal airfield, and the research lab grew further as part of NACA, getting more involved in rocket research, eventually becoming one of NASA’s main R&D sites, now called the Glenn Research Center. After the war the bomber plant, located on the south end of the airport, was used for soybean storage until it was reactivated in 1950 by General Motors, as the Cadillac Tank Plant, making army tanks for the Korean war, none of which ended up being used, due to a design flaw. The building continued to be used to make tanks, howitzers, and personnel carriers through the Vietnam War until it was closed in the mid 1970s, and later reopened as the exhibition center.