Trylon and Perisphere

The Trylon and Perisphere were two modernistic structures, together known as the "Theme Center," at the center of the New York World's Fair of 1939-1940. Connected to the 610-foot (190 m) spire-shaped Trylon by what was at the time the world's longest escalator, the Perisphere was a tremendous sphere, 180 feet in diameter. The sphere housed a diorama called "Democracity" which, in keeping with the fair's theme "The World of Tomorrow", depicted a utopian city-of-the-future. Democracity was viewed from above on a moving sidewalk, while a multi-image slide presentation was projected on the interior surface of the sphere. After exiting the Perisphere, visitors descended to ground level on the third element of the Theme Center, the Helicline, a 950-foot-long (290 m) spiral ramp that partially encircled the Perisphere.