Oxford Castle. Antique print of Oxford Castle, which is a large, partly ruined Norman medieval castle on the western side of central Oxford in Oxfordshire, England. Most of the original moated, wooden motte and bailey castle was replaced in stone in the 11th century and played an important role in the conflict of the Anarchy. In the 14th century the military value of the castle diminished and the site became used primarily for county administration and as a prison. Most of the castle was destroyed in the English Civil War and by the 18th century the remaining buildings had become Oxford’s local prison. Antique copper-plate engraving of a ground plan of Oxford Castle. Dated in the plate 7 March 1785.