A summer camp in Vermont. Our camp moved to its current property in 1986. The property we were moving to and that is our current location was a girl's camp, but it was inexplicably abandoned.. They left working trucks, a tractor, canoes, paddles, etc. There is graffiti all over camp from girl's who stayed at the camp, shit like "Betsy '56, '57, '58" but there is also some very creepy stuff.
A lot of the equipment that they left behind we still use, such as the canoes and the paddles.
There are lots of ghost stories made up by counselors about why the girl's camp closed, but in reality, nobody knows. I've looked it up to try and find out, but I can hardly find any information that the camp ever existed.
To make things VERY creepy: There was a wedding at our camp, and this old ~90 year old woman was being driven in, and she kept on insisting "I've been here before" and could even identify where buildings would be before she saw them. She said she had never been to a girl's camp before.
turns out that before it was a girl's camp, in the ~1920's, the campground was actually an sanitarium, and at a young age this women had been sent there for some reason.