I lived in California when the Haunted Mansion opened in 1968. I would have been seven at the time. I'm don't think I visited it right away, but it certainly wasn't long after that. Trust me, at that time, it was scary enough for a kid. Let's not forget that there were even initial rumors that the haunt was SO scary that a guest had a heart attack so the ride was rejiggered to make it less scary. That rumor is not true, but the initial room with its disappearing ceiling and hanging person/skeleton was enough to make a little kid say, "oh shit" back in the day. Of course shortly after the opening sequence things take a bit of a musical turn and things get less scary and more along the lines of creepy fun.
So here I am, checking the ride out on it's 50th anniversary and all I can say is that it is still a work of art. Very little has changed in the attraction and while a grown up me knows how all the props work, it's still an incredibly fun ride. I have to also mention that I did give it a second spin and was blissfully caught in the pitch dark when the ride broke down (to me, this was heaven).
In retrospect all I can say is "thank you" to Disney, of all people, who gave so many people a love of haunted houses. Those of us in the haunted house business use tips, tricks, themes and more that were all developed for The Haunted Mansion. I would encourage anyone and everyone to make at least one pilgrimage to the Haunted Mansion to see where things really began. I'm sure there were probably cheap carnival and other scares before it, but the Haunted Mansion has been the gold standard for fifty years and I hope for fifty more.