On August 9, 1969, the attraction officially opened to the public and has remained mostly unchanged, with the exception of the yearly conversion into 'Haunted Mansion Holiday' discussed below. Designers wanted to make the exterior look like a stereotypical run-down and decrepit haunted house, but Walt himself overrode the idea, claiming 'we'll take care of the outside and let the ghosts take care of the inside.' In what might be considered to be a unique twist to a supposedly 'abandoned' structure, the exterior appears pristine and the surrounding grounds are meticulously maintained.

Conceptual drawings were done for this concept, but the Museum of the Weird would be left on the drawing board due to the walk-through idea being shot down in favor of making the attraction a ride-through. At one point, it was conceived as a walk-through that would empty out into an exhibit called 'The Museum of the Weird'. The attraction went through many concept changes before its facade was completed in 1963, six years before it would open to the public, delayed by Disney's involvement in the 1964 New York World's Fair. Eventually, the decision was made to place it in New Orleans Square and thus the mansion's exterior was themed as an antebellum home. The house originally had a rural American design and was intended to be at the end of a crooked path that led away from Disneyland's Main Street, U.S.A.

Originally conceived in the mid-1950s by Walt Disney as a walk-through ghost house, artist Harper Goff was tapped to conceptually design the attraction.

11.3 Mickey's Great Adventure in Tokyo Disneyland.

4.9.1 The Endless Hallway and the Corridor of Doors.

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