|Mixbury, Oxfordshire, England|
|Type||Possible Motte and bailey or ringwork|
|Condition||Limited earthworks remain|
Beaumont Castle was a possible motte and bailey or ringwork castle built in the village of Mixbury, Oxfordshire, England. The castle was probably built by Roger d'Ivry following the Norman invasion of England. The castle was probably called Beaumont because it occupied a natural promontory overlooking a local stream. The castle was abandoned before 1216. Private excavations by two brothers from London in 1954–5 allegedly revealed a dungeon and an underground passage, although this discovery is disputed by scholars.
- Parishes: Mixbury, A History of the County of Oxford: Volume 6 (1959), pp. 251-262; accessed 11 June 2011.
- Parishes: Mixbury, A History of the County of Oxford: Volume 6 (1959), pp. 251-262; accessed 11 June 2011; Beaumont Castle Archived 2012-03-25 at the Wayback Machine, English Heritage, accessed 11 June 2011.