The S.K. Pierce Mansion in Gardner, MA, is known for reported paranormal activity including full-body apparitions, disembodied voices, slamming doors, and temperature changes, attributed to the spirits of its builder, Sylvester K. Pierce, his wives, other family members, and boarders who died on the property. Visitors to the haunted mansion have described encountering shadow people, foul odors, and objects moving on their own, with some attributing a lion-like roar to Sylvester Pierce himself. Visitors and owners have claimed to see the ghosts of Sylvester K. Pierce and his two wives, Susan and Ellen. Other spirits include family members like Edward and nanny Mattie Cornwell, as well as other unnamed dark entities. Reports include voices, chanting, and, notably, a loud lion-like roar, which is often said to be Sylvester Pierce expressing anger over his mansion's current state. Guests have reported physical phenomena such as hair being pulled, screens flying off windows, slamming doors, and sudden changes in temperature. Shadow people, foul odors, and moving furniture have also been noted.