Thru the many years the state of Pa. has grown and expanded their where many fortunes made and lost and towns which sprung up around the Coal ,Iron , Oil and lumber Industry which also found fortune and failure and in some cases have completely disappeared like the famous Pit Hole Ghost town which is now a state museum and park.
Many times only thing left where Grave yards and cemetery to become lost to time like Livermore a town removed when they flooded the town with a reservoir designed to protect Pittsburgh .
So finding a Mausoleum from a long forgotten town out in the middle of nowhere would be rare but it does happen.
Take the case of the tomb of Colonel Noah Parker near Emporium located in a one time Lumber town of Gardeau
Its sits there all by itself surrounded by forests and rattle snakes. With no apparent cemetery to go with it.
Some say its filled with treasure and the colonel is not even buried there.
The truth in this case may be stranger than true and involves Indians and Pirates
What ever the truth the whole back story to it is winding and complicated so I have included the following link to give you the whole story .The author of whom can give you a much more complete picture.
https://paoddities.blogspot.com/2019/08/colonel-noah-parker-and-myth-of.html