This was featured on unsolved mysteries and is the topic of books, and a movie called a place in the sun.
In the early 1900s Grace Brown was drowned by her fiance, Chester Gilette. Reports say that they have tried to pull the string on a light and they feel a cold hand, see her drowning, or see apparitions at the lake..
some guards say there that sometimes they will go off, when the building is completely empty.
And they will go off in a strange order, sometimes near the basement and then almost immediately near the stairs.
From outside you can see a man standing in the window sometimes.