In the 1970's, Imagineer extraordinaire Tony Baxter was charged with the task of revitalizing the Nature's Wonderland area in Frontierland. The project was divided into two phases. The first phase would see the removal of the Nature's Wonderland mine ride and the premiere of the Big Thunder Mountain runaway railroad thrill attraction. This new attraction had a much smaller footprint than it predecessor. Also, in the mid 60's, the Disneyland Railroad had been re-routed further north to accommodate the addition of It's a Small World. This would leave a large undeveloped area at the northern end of Frontierland, and the master plan was to fill this space with a brand new themed land to be called Discovery Bay. The inspiration for this area came from the Jules Verne and H.G. Wells science-fiction stories of the 19th century, and the entire area would exhibit a retro future look, an aesthetic that is often referred to today as "steampunk." Another inspiration for Discovery Bay came from two Walt Disney theatrical films, "20,000 Leagues Under the Sea" and "Island at the Top of the World." In fact, the entire land was betting on the success of the 1974 release of "Island at the Top of the World." Unfortunately, the film was a major box office disappointment, placing the future of this land in peril and would eventually lead to its cancellation. But good ideas never die, and many of the themes and ideas developed for this never-built area would eventually be revamped for the Tomorrowland equivalent found in Disneyland Paris known as Discoveryland, and in attractions later developed for Tokyo DisneySea in Japan. The area once designated for Discovery Bay would later feature Big Thunder Ranch, and today is the home of Star Wars: Galaxy's Edge.

Tomorrowland presented Disney Imagineers with a unique problem. How do you keep the future from catching up to the present? To fight this ongoing battle the land received major overhauls in 1959, and again in 1967. By the late 1980's time had again turned the land of the future into a land filled with outdated projections. Imagineers were sent back to the drawing boards to come up with yet another new Tomorrowland concept, giving rise to what would become known as Tomorrowland 2055. This seemingly arbitrary year was chosen as 2055 would be the 100th anniversary of Disneyland. Rather than trying to project a factual future, to keep the area more timeless a new science-fiction approach took hold. The new land would become an intergalactic spaceport of the future, where aliens would comingle with humans. The entire area would be buzzing with kinetic activity. Dramatic neon lighting would illuminate the refurbished structures. Giant pulsating geodetic and crystal rock formations would be scattered throughout the grounds. New upper level walkways, bridges and catwalks would give guests access to new shopping and dining experiences. Many classic attractions would remain, while several exiting and innovative new attractions would debut. The carousel theater would become the venue for a musical show performed by an all-alien animatronic cast. The second floor of the carousel building would house a laser shooting dark ride based on Disney's 1979 film, "The Black Hole." Replacing Mission to Mars would be a frightening encounter with a space creature based on Fox Pictures' "Alien" franchise. The Circle Vision Theater would become a new time travel experience. And to tie it all together, a new nighttime light parade would replace the Main Street Electrical Parade. The procession would be led by a giant UFO that would fly over Disneyland ushering in a cavalcade of friendly beings from another world. Marching and hovering aboard spacecraft floating down Main Street USA, they would celebrate their arrival through music, projections, and pyrotechnical effects. Due to the financial losses incurred during the opening of Euro Disneyland in Paris, the project was put on hold, and Tomorrowland 2055 became yet another unrealized concept in the annals of the Tomorrowland That Never Was.