However, the destruction of Jellyfish Fields would prove to be Plankton's downfall. Moments after Mr. Krabs was finally preparing to hand over the Krabby Patty Formula to his nemesis, Bikini Bottom was invaded by hordes of jellyfish aggressively seeking a new home. Realizing that the creatures would only stop their attack if Jellyfish Fields was restored, the citizens of Bikini Bottom aided SpongeBob in destroying Plankton's highway.
It also appeared in the end of The Great Patty Caper in an alternate timeline
It is unknown who the Shelly Superhighway is named after, although it could be named after seashells.
Another possibility is that Plankton used the name "Shelly" to hide his identity so people will approve of the highway; a plan that succeeded in tricking even Mr. Krabs.
The name "Shelly" could also reference Plankton's first name, "Sheldon."
The Shelly Superhighway seems to always end or start at the Chum Bucket. This was part of Plankton's plan, as the highway was also meant to draw away the Krusty Krab's business to his own establishment.
Squidward is the only one of the main characters that isn't involved in the destruction of the Shelly Superhighway.
The Shelly Superhighway has a corkscrew section.
The Shelly Superhighway makes lots of air pollution, which makes the sky turn a dark gray color and makes the clouds look like they are melting.