Ruthven National Historic Park near Cayuga, Ontario, preserves a grand Greek Revival mansion built in the 1840s by David Thompson, a prominent local figure. The estate, which includes the main house, outbuildings, and surrounding parkland, was featured on the Canadian show Knock Knock Ghost. The mansion has been associated with poltergeist-like activity reported by Parks Canada staff and visitors. Objects in the house have been found moved from their display positions, doors slam shut without wind or vibration, and some staff have described heavy furniture being found in different locations after the house was locked for the night.
The most striking reported phenomenon involves a rocking chair on the second floor that has been observed rocking vigorously by itself, witnessed by multiple people simultaneously. Some visitors have described hearing footsteps on the main staircase and the rustle of a woman's dress in the hallway. The estate's grounds, which slope down toward the Grand River, are also the site of occasional reports — figures seen near the outbuildings at dusk, and the sound of horse hooves on the gravel drive.
The mansion's lovingly preserved 1840s interior, with its period furniture and textiles, creates an environment where the past is physically present in every room.