The only two structures built for the World's Fair that are still there are the Amphitheater and the Sunsphere.
The Sunsphere re-opened to visitors in 2007 and in 2008, businesses started moving in too.
In a classic Simpsons cartoon episode, Bart and his friends take a road trip to the World's Fair.
"Next stop Knoxville's World's Fair and its fabulous Sunsphere!" they proclaimed.
Trouble is, the cartoon characters showed up 14 years too late and the Sunsphere, well, it was full of wigs.
"You're welcome to go up there if you want to see 16,000 boxes of unsold wigs," the wig shop owner told them.
When the Sunsphere was under construction, a wig shop was not part of the plans...
During the World's Fair, visitors could pay $2 for an elevator ride up to an observation deck and a full service restaurant.
The restaurant and the observation deck closed when the World's Fair ended and the Sunsphere did not house another business for 25 years.
"What was depressing when we first came to the Sunsphere is it was abandoned, there was nobody here. It was boarded up, boarded up is a little overstatement, but you couldn't come, no one could come and visit," Jason DeBord said.
Jason DeBord is with Cardinal Enterprises, the development company in charge of the Sunsphere.
Cardinal moved its offices to the 7th floor of the Sunsphere about three years ago.
"It's a good place to come and do your work every day," DeBord said.
The city of Knoxville runs an observation deck on the 4th floor that is open to the public.
"On the 5th floor we recently signed a new tenant, (that) is going to be putting in a new ultra lounge there called the Icon," DeBord explained.
The 6th floor is a special events floor where clients bring in their own caterers.
"We do a lot of sorority parties, fraternity parties, etc. We do a lot of things. We're the only surviving structure besides the Amphitheater, so now we're doing weddings down there through PBA and then they come up and have their reception here," Sara Spangler said. She organizes and books Sunsphere events.
The 8th floor, the top floor, is Half Off Depot dot com, an internet based deal site.
"One of the big selling points for them is, hey, our offices are in the Sunsphere. I've actually heard people on their first day of work calling their parents and saying, hey, mom I'm in the Sunsphere, and thinking how cool that is," DeBord said.
The monument to the sun complemented the fair's theme back in 1982, "Energy Turns the World."
And 30 years later, the Sunsphere has a renewed vibe and energy.
"Just having thriving businesses here every day, passing people on the elevators, then having the observation desk, seeing all the different visitors coming in. The energy's just high," Spangler said.
When asked about the Sunsphere's future, Jason DeBord says the future is now because it's been realized.
"The true vision of the Sunsphere was to get it re-opened and to have people be able to come and experience it and remember the World's Fair and have such a great view of the city," he said.
And all these years later, visitors still make comments...
"They'll say 'where's the wig shop?' They'll laugh and think that's just the funniest thing in the world. And it is funny, but when you've heard it 400 times it doesn't quite seem as funny, especially to a Knoxvillian," he said.
The public is welcome to come up to the observation deck.
One change from the World's Fair is access is now free. One similarity is the view is still spectacular.