Oxford Castle is a mostly ruined medieval Norman castle in central Oxford It has a long and eventful history. Most of its original motte and bailey structure was replaced in stone in the late 12th or early 13th century and the castle played an important role in subsequent medieval conflicts. 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. This closed in 1996 and was redeveloped as a hotel and visitor attraction. And so it remains.The oldest remaining part of the Castle, St George's Tower, dating back to Saxon times, is on right of frame.