i've heard that some evidence exists that the Aztecs may have reached as far north as Oak Island, a suggestion being that they built something there centuries before whatever treasure was supposedly hidden there ever came to be.
'Cause everyone knows the Aztecs, Maya* and Inca were the only game in town in the entire Americas, and if something old-looking was found anywhere remotely near it had to be one of them. That or a lost thirteenth tribe of Israel.
*Oops, sorry. The MayansM Y S T E R I O U S L Y C O L L A P S E D from existence.