Welcome, foolish mortals… to “Happy Haunts Materialize: Fifty Spirited Years of The Haunted Mansion,” Disneyland’s new tribute to its world-famous ghostly retreat in New Orleans Square, which celebrates its 50th anniversary this August.

Starting this morning, Disneyland guests can find a scary amount of concept artwork, maquette sculptures, and fascinating behind-the-scenes information on how Walt Disney Imagineers first brought The Haunted Mansion to life (or should I say afterlife?) back in 1969.

Watch The Haunted Mansion 50th Anniversary Exhibit at Disneyland:

The “Happy Haunts Materialize” exhibit is set up in Disneyland’s iconic Main Street Opera House, home of the beloved Great Moments with Mr. Lincoln attraction. Inside the Opera House’s lobby– also known as the Disney Gallery– you’ll find display cases and framed paintings containing many of the key designs that proved indispensable in The Haunted Mansion’s conception and execution.

Legendary Walt Disney Imagineers like Marc Davis, Claude Coates, Ken Anderson, X. Atencio, Rolly Crump, Blaine Gibson, Duane Alt, Jack Ferces, and Joe Kaba are celebrated in an exhibition that also makes note of the hilariously pun-derful tombstones that honor their names in The Haunted Mansion’s graveyard.

How The Haunted Mansion materialized:

“Since its hinges first creaked open in 1969, The Haunted Mansion has welcomed generations of guests and ghouls alike to tour the ghostly retreat. Yet contact between the earthly plane and the boundless realm of the supernatural was not easy to establish: it took over fifteen years for the happy haunts of The Haunted Mansion to materialize.

During that time, Walt Disney Imagineers were faced with the “chilling challenge” of deciding what a haunted house attraction at Disneyland should be. Should the ghosts be grinning or should they be grim? Should the attraction focus on the “hot and cold, running chills” of its setting or the “wall-to-wall creeps” that inhabit it?

In celebration of 50 years with our Grim Grinning Ghosts, the Disney “Ghoul-ery” invited you to a special “viewing” of The Haunted Mansions residents as they appeared in their corruptible, concept state. Kindly step all the way in to explore the eerie evolution of The Haunted Mansion’s design, from a walk-through attraction at the top of Main Street, USA, to a “Museum of the Weird,” to the ghoulish delight that we know today. As you trace the attraction’s “disquieting metamorphosis,” you’ll discover how Walt Disney Imagineers made final arrangements for a Haunted Mansion that was both silly and spooky by building off the sympathetic vibrations of each other’s ideas.”

“Happy Haunts Materialize: Fifty Spirited Years of The Haunted Mansion” is now open in the Main Street Opera House’s Disney Gallery at Disneyland in Anaheim, California.