As a former Knoxville resident, I can attest that we are usually happy to see any mention of our city in the media at all. Unfortunately, one of our claims to fame, the Simpsons episode "Bart on the Road" (Season 7, episode 20) is mistaken about the history of one of our most notable monuments, the Sunsphere.

Knoxville, as you probably don't know, is a city in the eastern portion of Tennessee that is known for its pair of giant orange balls, the Women's Basketball Hall of Fame and the aforementioned Sunsphere (and also a college football team and rather nice national park, but that's not what we are here to talk about).

In "Bart on the Road," using a faked driver's license Bart, Milhouse, Nelson, and Martin get a car and go on a road trip. The decide to head to Knoxville to see the World's Fair, mentioned as housing a giant motorized Hungarian Rubik's cube (this is accurate-read about it here) and the Sunsphere.

On the way in they pass a welcome to Tennessee sign, with the motto "Tennesseein' is Tennebelievin'", although unfortunately the actual welcome signs just say "Tennessee Welcomes You". Shortly afterward we are provided with an overhead view of the World's Fair Park circa 1996. While I have to admit the image captures the general "feel" of the place in the mid 90's (kind of run-down and scruffy), it's an inaccurate description once you get into the details. For comparison, here's a map from the fair's heyday, and here's a more recent picture. Note that the Sunsphere has never been out by itself, instead it's adjacent to buildings and a large bridge. There's also no sign of the Tennessee Amphitheater, one of the few World's Fair buildings to still be in use in 1996. Also I can personally attest that the water was inexplicably dyed a dark greenish blue at the time. The oddly sloped building adjacent to the water in the Simpsons image is the US pavilion, which was demolished in 1991. It would have not been present in 1996 when Bart came to visit.

Bart & co. then meet a man standing in front of a wig shop. He tells them the World's fair ended in 1982, 14 years before their visit. This is correct. In fact, the Knoxville World's Fair was the last successful fair held in the USA (a fair two years later in New Orleans was the last fair in the USA, but declared bankruptcy midway through and suffered low attendance). Knoxville's fair netted a total of only $57 in profit, but managed to attract 11 million visitors, an excellent showing. Unfortunately, after the fair was over, the park largely fell into disrepair until it was finally fixed up in the 00's.

And now we come to the bad Wig history. Because the Sunsphere was never called the Wigsphere, and never housed any wigs (aside from any that might have been worn by visitors). It also never fell over thanks to to a rock thrown by Nelson, obviously. During the fair, the Sunsphere housed an observation deck and restaurant. It was occasionally mooted through the 80's and 90's as a potential office space or restaurant, but continued to be mostly vacant, and there was no wig shop in the area nearby it. In the late 90's the observation deck level was re-opened, still with the displays from the original fair. The other levels were unused and closed off (but, ah, not very securely closed off) and were definitely empty of wigs or much of anything else. In the late 00's and early 10's the place was finally remodeled and now hosts an observation deck and bar/lounge.

Later in the episode, Lisa states that Knoxville is adjacent to Oak Ridge Tennessee, "birthplace of the nuclear bomb", and points it out on a wall map. The bombs weren't actually assembled in Oak Ridge, but the uranium and plutonium used for them was refined there. So if not the birthplace, it was probably the gestation place for the atomic bomb (The story of Oak Ridge's secret city is a pretty interesting read). Oak Ridge didn't contain any nuclear power plants, and most of the nuclear production facilities were closed by 1996, but it probably still reasonably counts as a "nuclear site", explaining why it is on Homer's map. Incidentally, the location Lisa points to on the map is accurate for Oak Ridge, but the map is missing markers for several nuclear power plant sites in TN.

So in conclusion, the Sunsphere was never full of anything as exciting or interesting as wigs in the mid 90's.