The Perisphere was a tremendous sphere, 180 feet (55 m) in diameter, connected to the 610-foot (190 m) spire-shaped Trylon by what was at the time the world's longest escalator.
The Perisphere housed a diorama by Henry Dreyfuss called Democracity which, in keeping with the fair's theme "The World of Tomorrow", depicted a utopian city-of-the-future.
[1] The Theme Center was designed by architects Wallace Harrison and J. Andre Fouilhoux, with the interior exhibit by Henry Dreyfuss.
The structures were built in Flushing Meadows Park in Queens, New York and were intended as temporary with steel framing and plaster board facades.
[citation needed] The Trylon and Perisphere became the central symbol of the 1939 World's Fair, its image reproduced by the millions on a wide range of promotional materials and serving as the fairground's focal point.