From 1973 until 1994 Space Mountain was sponsored by RCA. Guests entered Space Mountain through an entrance building located in Tomorrowland which featured three large RCA logos as well as an original "four seat" ride vehicle, encased in a clear case. Inside the vehicle sat a family consisting of a father, mother and two children. Before guests entered the "entrance portal", they would pass a large quote on the wall which read:
{{Quotation|"ONE GIANT STEP... Dedicated to the men and women whose skills, sacrifice, courage and teamwork opened the door to the exploration of man's exciting new frontier...outer space. Because they dared to reach for the stars and the planets, man's knowledge of his universe, earth and himself has been greatly enriched. Presented by missile, space and range pioneers. January 15, 1975."}}<ref> http://www.omniluxe.net/wyw/sm.htm </ref>
Just after entering the building, guests boarded a descending, moving ramp. On the right side of the ramp, guests could see RCA's mascot, Nipper the Fox Terrier and a phonograph machine inside a flying saucer. At this point in the attraction, RCA's Space Mountain theme song- "Here's To the Future and You" would begin to play. Further down the ramp guests could look out convex windows and see the Star Corridors, a series of different space themed displays. One display for example, showed an astronaut riding his moon buggy in space. On the left hand side of the descending ramp, a series of RCA products were displayed. The reason that guests had to be lowered, was because the queue actually ran underneath the [[Walt Disney World Railroad]] to the lot where Space Mountain is actually located. After guests finished descending, they reached the "zig-zag corridor". Here windows allowed guests to see out into space. Things that could be seen out these windows included:
*Shooting Stars
*And finally, a family riding the Space Mountain ride vehicle in space.http://www.omniluxe.net/wyw/sm.htm </ref>
After passing through the zig-zag corridor, guests finally reached the loading area. Here they watched a safety video featuring Astronaut Gordon Cooper, before boarding their ride vehicles on either the Alpha or Omega track (the two tracks were identical except for the fact that Alpha track was ten feet longer).