Norman architecture, also known as the English Romanesque, is punctuated by the dramatic heights of Durham Cathedral. Norman architecture is named for the Norsemen (Vikings) who settled in France (Normandy), converted to Christianity, and attacked the British Isles in 1066, with William the Conqueror as their leader. Durham Cathedral is evidence of William the Conqueror’s Christian legacy as one of the tallest cathedrals in England. But it is not simply size that makes Durham Cathedral innovative, it is the manner in which Durham’s builders were able to achieve such height: ribbed vaults.