Newbury Castle
 Newbury Castle is the name of an English adulterine castle built by John Marshal during The Anarchy. It is located west of the town of Newbury in the English county of Berkshire. The Castle is mentioned in the L'Histoire de Guillaume le Marechal (History of William the Marshall) wherein it describes King Stephen as besieging the castle in 1152 and holding Marshal's son William Marshal as a hostage against Newbury's surrender.