1904 The Louisiana Purchase Exposition World's Fair opens in St. Louis, Missouri.
1933 The Century of Progress World's Fair opens in Chicago, Illinois.
1962 The Seattle World's Fair (Century 21 Exposition) opens. It is the first World's Fair in the United States since World War II.
2010 Hailed as the largest World's Fair in history, Expo 2010 opens in Shangai, China.