PRN 30083 West of church are traces of the foundations of a large moated mansion or castle, supposed to have been built in the reign of King Stephen by one of the Bussey Family, who were resident here until c1609. The site is a low circular motte with a bailey to south. Foundations are traceable both on the motte and outside the bailey. Two roads and ponds exist within ridge and furrow; other earthworks are amorphous. Survey 25inch revised.{1} An irregular ring motte or inner enclosure, large enough to have contained main buildings, with bank highest in south-east corner and ditch. Traces of light outer bailey to south. During a watching brief from Haydor to Aisby, material from the collapsed outer earthworks of the castle was found on the south side of the site. However, in the absence of dateable material the association can only be tentative.{8}{10}{11} A medieval ringwork and bailey situated on Castle Hills, occupied by a manor house in the later medieval period. In 1086, the land was held by Guy de Craon as part of his manor of Osbournby. By the beginning of the 13th century, the manor of Haydor was held by a tenant, Roger de Rudston, and in 1343 documentary sources record the presence of a manor house with outbuildings, a dovecote and a garden. By the 16th century, the manor of Haydor had descended to the Bussey family.{13} Creasy noted in his History of Sleaford the former existence of 'an edifice of vast size. The foundations...are singularly traceable, and...the immense banks of earth...speak...of its ancient strength and glory'.{14} The pond at the north-eastern corner of the monument is not included in the scheduling, nor are the three ponds to the east. All fence posts and water troughs are excluded from the scheduling, although the ground beneath them is included.{13}