This report documents the discovery, excavation and preservation of a Norman moated stone manor house found in 1984 at the Mount House, Witney. The trial excavations that were made in advance of housing development, revealed groups of buildings surrounded by a curtain wall and moat. Further excavations in the north-west and south-east parts of the complex uncovered a massive and well-preserved tower and attached range of the first half of the 12th century which was progressively enlarged by a chapel, a central pier, a raised terrace and a garderobe block. The buildings were further modified in the later medieval period. Coins in robber trenches indicate that some buildings were demolished during the English Civil War, though others were maintained. The front cover shows Nathaniel Buck’s early 18th century engraving purporting to show the remains, which were systematically demolished in the mid-18th century to make way for a new house. The site remained in the ownership of the Bishops of Winchester until 1862, when it was purchased by the 6th Duke of Marlborough. The present house was built c 1904. The site was purchased by Oxfordshire County Council in 1993, and the tower is now on display to the public.