The Century 21 Exposition is best remembered for the creation of Seattle's Space Needle and Alweg Monorail. Much of what was created still exists today, including the United States Pavilion which is now the Pacific Science Center.

This Exposition was actually Seattle's second international exposition, preceded by the 1909 Alaska-Yukon-Pacific Exposition.

Alweg Monorail with Space Needle in background

LINKS:
History of the Century 21 Exposition - from HistoryLink.org
The Impact of the Cold War on Seattle: The 1962 World's Fair - from the Center for the Study of the Pacific Northwest
The Space Needle - the official site
Seattle Center Monorail - the offial site
Seattle Center - the legacy site
A Fair to Remember: Seattle Center at 40 - from the Seattle Post-Intelligencer
World's Fairs are a Dying Breed - from the Seattle Post-Intelligencer
Friends of the Monorail - site advocating the extension of the existing monorail.
A Model for the Future - Article from The Seattle Times in 1962.
Alweg Monorail - the monorail's manufacturer
Pacific Science Center
Excerpts from the Souvenir Program - hosted by Scruff
Scouting at the World's Fair
1962 Century 21 Exposition Seattle World's Fair - images posted by azzurrolou on Flickr
Century 21 Exposition Space Needle Design - cut-away illustration and alternative designs