I think that they are fake, because even though this would be classified as historical fiction, and it has events based around history, i doubt that something like that would be plausible. I may be wrong, but I doubt that there is an invisible map on the back of the declaration of independence and that abandoned mine shaft in a church as there were in the first National Treasure. I don't totally remember the second National Treasure, but I may watch it again soon. Either way I still really liked the premise behind the National Treasure movies.