Here's a great little treat for the day! At one point in its early development, a walk through version of the Haunted Mansion was planned by the Imagineers. This piece of concept art was shown as part of the 50th Anniversary display in Disneyland's Opera House.
As you can see, the walking tour would have included a stop at the famous ballroom. Even though it would have seriously changed the capacity of the attraction, imagine what a kick it would be to walk the home and explore it at your leisure. I would have spent hours in there!
(Art copyright The Walt Disney Company.)