Chillingham Castle is a medieval castle in The Village of Chillingham in the northern part of Northumberland, England. It was the seat of the Grey and Bennet families from the 15th century until the 1980s. A large enclosed park on the castle grounds is home to the Chillingham Cattle, a rare breed, consisting of about 90 head of cattle. The castle is a Grade I listed building.
Its current owners market the castle as being the most haunted castle in Britain. It has been investigated on television and radio (namely, Most Haunted, I'm Famous and Frightened!, Scariest Places On Earth, Holiday Showdown, Alan Robson's Nightowls), Ghost Hunters International, and is the subject and setting of the documentary, A Blood Red Sky (2013). Some of these ghosts are written about are referred to in a 1925 pamphlet by Leonora, Countess of Tankerville. Others, such as John Sage, are of more recent invention.
The most famous ghost of the castle is the "blue (or radiant) boy", who according to the owners used to haunt the Pink Room in the castle. Guests supposedly reported seeing blue flashes and a blue "halo" of light above their beds after a loud wail. It is claimed that the hauntings ceased after renovation work revealed a man and a young boy inside a 10-foot-thick wall. Documents dating back to the Spanish Armada were also found within the wall.