Its true, P.A. used to be the route for entire payrolls for our troops in 1812, stationed along Lake Erie. I'm talking wagons full of gold or silver coins. There are several accounts of them being lost or some of the hold or silver buried to avoid capture. However, in at least one case it was apparent that a rogue ex-military officer may have launched his own expedition to find it and may have actually succeeded. It could be that some of these treasures existed but were actually recovered long ago.
There's another story of a platoon of the Continental Army having ditched quite a bit of equipment somewhere in the Alleghenies as they were being followed and it was weighing them down. It was never found and no leads came up that I know of. However, if you recall the story of the Winchester rifle that was found after 150 years still leaning against a tree in a National Park, that is TRUE. Nad if that can happen so could a bunch of cannons and other gear get dragged by horses into the woods and not be seen again for a long time.