Don Firth: Wow, I never knew that the 1964-65 New York World's Fair (the one with the Unisphere) wasn't officially sanctioned. According to this site – http://naid.sppsr.ucla.edu/ny64fair/index.html – the Bureau of International Expositions allowed only one US world's fair per decade, and limited world's fairs to one-year runs. The NY World's Fair ran for a total of 360 days, but over the course of two years (April to October each year). I wonder why they were allowed to call it a "World's Fair"?