In New Orleans Square, near the Haunted Mansion, there is what appears to be an old crypt. Covered with bricks and dated 1764, the crypt is built into to the wall along the Rivers of America.
There are lots of stories and rumors about this odd Disney Detail. The crypt might have been part of the wealthy pirate backstory, originally meant to tie the Haunted Mansion to Pirates of the Caribbean. It may also be an attempt to link the manor to Jean Lafitte, a pirate & privateer in the New Orleans area, who fought against the British in the War of 1812. Another story claims that the date of 1764, is a tribute to one of the Imagineers who helped create New Orleans Square.