When the Haunted Mansion dark ride opened in Disneyland on August 9, 1969, it was an instant hit for the theme park. Within a week of the attraction’s opening, the park experienced the highest number of single-day attendance (at the time). It’s easy to see why; the catchy music that includes songs like “Grim Grinning Ghosts” (written by X Atencio), the 999 delightful haunts that entice with “room for one more”, the Doom Buggies that whisk you through the twisty home and its neighboring graveyard, and it’s consistent adherence to Walt Disney’s theme of updating the park and its rides while maintaining tradition. The level of detail and effects makes the Haunted Mansion as impressive today as it was 50 years ago.

Of course, anticipation likely played a key factor in the attraction’s opening day success. Opening day might have been in 1969, but the exterior had been completed in 1963. It remained behind locked gates for years, piquing the curiosity of park attendees and spurning rumors that blossomed into full blown urban legends about how the ride had once been opened but had to close for being so scary. Or how someone knew someone who knew someone else who’d had a heart attack on the ride. The truth was that Walt Disney and his Imagineers were busy with the 1964-1965 New York’s World Fair. After his death in 1966, the attraction underwent a redesign, incorporating a lot of the technology introduced at the World Fair.

The idea for a haunted house in Disneyland had existed since the beginning, when the park was still being planned back in 1952. It had initially been suggested that the exterior match the ghoulish interior, but Walt shot it down, famously saying, “We’ll take care of the outside and let the ghosts take care of the inside.”

While the Haunted Mansion might be one of the most family-friendly of haunts, horror still served as a vital part of the research process. In 1960, Imagineer legend Rolly Crump (a designer behind the Haunted Mansion, Enchanted Tiki Room, and It’s a Small World) accompanied Walt Disney to see 13 Ghosts in 1960 for inspiration. It’s probably no surprise for anyone familiar with the ride that 1963’s The Haunting also played a major influence- hello hallway with stretching doors.

Though the mansion might be home to 999 ghosts, there are a few standouts that have captured hearts over the years. The hitchhiking ghosts- referred to as “Gus” (the Prisoner), “Ezra” (the Skeleton), and “Phineas” (the Traveler)- that attempt to hitch a ride on your doom buggy before the ride ends. Madame Leota, the head of a psychic medium encased in a crystal ball; she’s voiced by Eleanor Audley (Maleficent in Sleeping Beauty) and played by Leota Toombs. The Bride was a skeletal corpse with a glowing red heart; its beating sound filled the attic space in which she occupied. She’s since been updated to Constance, the Black Widow bride with a string of dead husbands, and an appearance that’s less corpse-like. And the most infamous of all, perhaps, was the ghost originally intended to be The Bride’s suitor- the Hatbox Ghost.

The Hatbox Ghost existed in the same attic space as The Bride, his head set to disappear and reappear in time to her heartbeat. But the effect didn’t really work, not with the attic’s lighting, and so it was removed shortly after the attraction had opened. Before long, the rumor mill speculated the Hatbox Ghost was simply deemed too scary to be included. He didn’t make his return to the attic or the ride until 2015.

Even without the consistent updates to keep the mansion fresh and 50 years of extensive history behind it, the uncanny level of detail and story makes the Haunted Mansion a ride with endless revisit appeal. No matter how many times you’ve ridden, there’s always something new to spot, whether it’s a reference, secret, inside joke, or a wry wink to park history. It never gets old.

There’s a reason there’s no shortage of highly coveted merchandise dedicated to the dark ride, from park exclusives like tiki mugs to even a Marvel comic book series that debuted in 2016. It remains one of Disney theme parks’ most beloved attractions. Disneyland’s official tagline is “The Happiest Place on Earth,” but for horror fans, that tagline is best suited to describing the Haunted Mansion. Here’s to 50 more years of spooky haunting. And that Guillermo del Toro may someday get to make his cinematic adaptation of this timeless ride.

“Hurry back! Hurry back! Be sure to bring your death certificate… if you decide to join us. Make final arrangements now! We’ve been dying to have you…”