What attraction/ride do you wish you had seen/ridden while it was in the parks. Not something long gone but an attraction/ride that was in the park when you were there that you didn't experience but was then gone so you never saw/rode it. For me it was the Disneyland Peoplemover and the Country Bear Jamboree. My first trip to Disneyland was in 1993 and both of those attractions were still there but I didn't have the wherewithal to ride them at the time. I have since experienced both the Peoplemover and CBJ in WDW but it's not the same.
For WDW it would be Horizons. It was definitely up and running when my family visited when I was a baby, but I obviously don't remember if we went on it. We returned when I was older during its "seasonal" era, and I have no memory of ever doing it, so I think we must have skipped it At DL, it is certainly Rocket Rods, which was actually up and running during a visit circa 1998. It had really long lines so we intentionally waited until the end of the day, to get in line right before the park closed so to not 'waste' any valuable park time in the queue. We entered the queue right as the park was closing, and my brother made some snide comment that upset my dad after a long day in the park, and he stormed off, forcing us all to follow him to the car. When we next returned to DL, Rocket Rods had closed for good I also would have loved to have seen the Castle Mystery Tour at TDL, even though I don't speak any Japanese. It must have been operating during my first visit, but I was completely unaware that it even existed at that point (way back when they were still using ticket books)
I learned my lesson with missing CoP when it was at DL (even though I may have been too young to appreciate it). And so I make up for it by seeing it at least 2-3 times whenever I make it to WDW. And knowing that both Ellen and GMR would soon be moving to YesterWDW, I made a point of riding both multiple times (and catching both scenarios of GMR) on my Fall 2016 visit. As to Rocket Rods, don't beat yourself up. It wasn't much (and it certainly failed miserably as a West Coast version of Test Track), and seeing CircleVision reduced to queue entertainment (I still cannot bring myself to set foot in the DL Buzz) didn't exactly help my reaction to RR. And we now DO have a West Coast version of TT; it's in the newest section of DCA, and we call it RSR.
For me, I would love to be able to board a time machine and visit Disneyland during its first year. The original Tomorrowland is hard for me to picture. That section of the park pre-Matterhorn with the giant mound of dirt. It would be fun to walk through the park in 1955 knowing what would be.
