Yes, Yomamma, there is an Oak Island.
Most people believe the pit contains Blackbeard's treasure. A few coins and artifacts have been recovered. But nothing definitive.
An alternative theory connects it to the Earl Sinclair of Orkney, the Freemasons and the Knights Templar. Supposedly the Earl came exploring, following some old tales/sagas, and the Templar treasure was buried on Oak Island. Before you ask, yes these are the Sinclairs of Rothesay Chapel, as featured in the Davinci Code and Holy Blood, Holy Grail. (cue spooky music)