Note: New information was added at the end of the post in January, 2012.
The solid, factual core behind today's topic is plenty fascinating in its own right, but the phenomenon goes beyond that core. If you extend it both backwards and forwards in time, what was merely a fascinating example of "lost imagineering" (to borrow a phrase from 2719 Hyperion), becomes something mysterious and intriguing and perhaps a little ominous as well. Something wicked this way comes.
We will start where everybody starts when discussing this topic. There is a curious, bricked-up, sunken archway in the esplanade along the river front, out in front of the Haunted Mansion.
The plan called for a crypt next to the Mansion that led into an underground catacomb of treasure and dead pirates, culminating in a pirate-themed hideout on Tom Sawyer Island. The pirate theme would have focused on Jean Laffite, a real-life pirate from the early 1800s in New Orleans. Laffite’s name might be familiar to frequent Disneyland visitors from the Pirates of the Caribbean loading zone, where a sign reads "Laffite’s Landing." The date 1764 was derived by subtracting 200 years from the birth date of one Imagineer who worked on the project. [Editor's note: this was Matt McKim, son of legendary Imagineer Sam McKim.] FURTHERMORE: Before its replacement with La Petite Patisserie, there was also a Laffite’s Silver Shop in New Orleans Square. Having a Jean Laffite identified as the "owner" of the Haunted Mansion would have united Pirates of the Caribbean with the Mansion and the island into one underlying theme, an unusual feat for an entire land. Though unrealized, the plan lives on in the form of this barricaded "crypt."