This story was told to me by my office mate, who only told me about his one and only ghostly encounter after much prompting.
There is a large old house called the Anderson Mansion on the edge of town. It was built by a wealthy banking family in the area. The Anderson's had about ten children. Several of the children passed away in the house from normal childhood ailments that were so deadly at that time in history. The family fell upon hard times and abandoned the house in the late twenties. The house stood empty for many years until it was eventually purchased by the city and became the town's historical museum. The house was still standing empty in the 1950's when my office mate (who was in his early teens at the time) and three of his best friends decided to go exploring in the house late one night. They climbed through a broken kitchen window and by flash light went through all the downstairs and upstairs rooms without anything weird happening. Eventually, they came across the basement door and went down into the basement At one end of the basement was a large door that my office mate thinks was made of concrete. According to him, the door was incredibly hard to open, because the bottom of the door dragged against the floor. Also, the sheer weight of the door did not help matters. It took all four boys five to ten minutes of tugging to get it opened enough for them to squeeze through the opening.They entered the room to find a small cot tucked in a corner with several old blankets still on it. They were standing around joking about what kind of freak would be kept locked in such a room, when the temperature in the room dropped dramatically. Then the large door - that took them so much effort to open - began to close by itself. They freaked out and were able to hold the door open enough to escape. The four boys fled the house as quickly as possibly. When my office mate got outside , he realized that he was bleeding. He had a huge scratch that looked like a claw mark running down the hand he had used to hold the door open so that they could escape. He ended up going to the hospital to get several stitches. I have toured the house several times, but the tour never goes down into the basement.