For Walt Disney, stasis was a kind of death. He wanted his films and parks to continually be improving, pushing boundaries, and leading the charge into the future. It’s why he said that Disneyland would never be truly complete and why he resisted calls to make sequels to short films like the Three Little Pigs. As he said, “You can’t top pigs with pigs.” He always wanted things to keep moving forward, plussing the experience for his Guests and fans around the world.

Walt believed in innovation and progress, in the idea that with a little ingenuity and hard work the world could be made better. This vision inspired the creation of the original Tomorrowland, and his early visions for Epcot. It was also the driving idea behind the classic Carousel of Progress Attraction.

Here are seven facts about the great, big beautiful tomorrow created by Walt Disney in the Carousel of Progress.

1. Edison Square

While Carousel of Progress did not officially come into existence until the 1960s, its roots trace back to the early years of Disneyland. Walt Disney wanted to build a land called Edison Square, which would include a show hosted by a character named Wilbur K. Watt who led Guests on a tour of the evolution of electricity.

2. Progressland

The Carousel of Progress began as part of Disney’s work for the 1964 World’s Fair in New York. It was the main feature of Progressland, a collaborative effort between General Electric and Disney.

The pavilion at the World’s Fair included items like demonstrations about thermonuclear fission, the model of an electric city, and a unique theater experience with Audio-Animatronics where guests followed the life of one family from the 1880s to the 1960s and watched how electricity affected their lives. This last Attraction was the Carousel of Progress and over the course of the Fair, as many as 4500 Guests a day saw the show.

3. The Sherman Brothers

Richard and Robert Sherman, who also wrote such classic Disney music as the songs of Mary Poppins and It’s A Small World (After All), composed the music and lyrics for the Carousel of Progress theme, titling it There’s A Great Big Beautiful Tomorrow. When the Attraction moved to Walt Disney World in the 1970s, they wrote a new theme titled The Best Time of Your Life. A third song, titled New Horizons was written by the Sherman’s but ultimately not used. In 1993, Disney brought back the original There’s a Great Big Beautiful Tomorrow song to the Attraction.

4. Rex Allen

In the original incarnation of the Attraction, actor Rex Allen served as the voice of the father. Allen’s association with Disney included over 40 appearances in Disney Westerns. Outside of Disney, Allen was known for composing over 300 songs, and recording a version of Artie Glenn’s Crying in the Chapel. He also appeared in television programs like the western Frontier Doctor.

Later incarnations of the ride replaced Allen as the voice of the father, but he returned to the Attraction in 1993 as the voice of the grandfather.

5. Andrew Duggan

In 1975, actor Andrew Duggan became the voice of the father character on the Carousel of Progress. Several other key changes occurred, with the song The Best Time of Your Life replacing There’s A Great Big Beautiful Tomorrow and an ending that featured a New Year’s Eve scene set in the 1970s.

Outside of his work with Disney, Duggan had over 180 acting credits ranging from television to film.

6. The End of the G.E. Era

General Electric’s association with the Carousel of Progress came to an end in 1985. Disney temporarily closed the Attraction to scrub all references to G.E.

7. Jean Shepherd

Jean Shepherd, best known as the narrator and co-author of the classic film A Christmas Story, became the voice of the Carousel of Progress’s father in 1993. The change was accompanied by a change of name, with the Attraction being re-branded Walt Disney’s Carousel of Progress and was part of the overall changes to Tomorrowland. The attraction also added a new ending, depicting home life in the 2000s, as envisioned at the time.