The Custer House, a replica at Fort Abraham Lincoln, is considered haunted due to paranormal activity reported by guides and visitors, including sounds of a ball breaking on a billiard table, seeing an apparition of a woman in a dark gown looking over the fort, and a general feeling of chilling presence, leading to many paranormal investigations and annual events like the Haunted Fort. Guides have reported hearing the distinct sound of a ball breaking on a billiard table, only to find no damage or broken ball when investigated. Visitors and guides have reported seeing an apparition, sometimes described as a woman in a dark gown, looking out over the fort from a window. There is a general chilling feeling or sense of "things dying off" within the house that some people experience.