Killaghy Castle is a Norman castle which stands 300 yards from the village of Mullinahone. Originally, in 1206, it was a Motte and Bailey, which is still visible to the left of the castle. The St. Aulyus lived there for 8 years and then erected a stone castle to take the place of the Motte and Bailey. This had four floors and a stone spiral stairway. During Tudor times a long house was added to the rear of the castle. Between this and 1800 two other buildings were added, making Killaghy what it is today.The original owners were Cromwellian planters by the name of Greene who in turn, through marriage, passed ownership to Despards and in turn to Wright. The castle has been owned by Watson, Fox,Naughton, Bradshaw, and Sherwood.