When Magic Kingdom Park opened at the Walt Disney World Resort on October 1, 1971, one of my favorite attractions – The Haunted Mansion – also opened its doors.

Located in the Liberty Square area of the park, guests could embark on a spooky tour through the final resting place of “999 Happy Haunts.” Guided by a Ghost Host, guests head through a spooky library with marble busts with watching eyes, visit a music room with a mysteriously invisible piano player, are guided through Madame Leota’s seance room, enter the ballroom for a “swinging wake” and more.

The attraction astounded guests on opening day – much as it continues to do today. Only a few additions have been made over the years: the mansion’s graveyard expanded in 2011, adding a mass of spooky new tombstones and crypts that guests can interact with on their way into the attraction. (Mansion fans won’t want to miss our behind-the-scenes video above, which shows how some of these markers are actually nods to the attraction’s former residents).

Today, The Haunted Mansion is one of several “haunted”-themed attractions you can find at Disney Parks around the world, including similar attractions at Disneyland park and Tokyo Disneyland, as well as Phantom Manor at Disneyland Paris and Mystic Manor at Hong Kong Disneyland.