Dover Castle has dominated the White Cliffs since it was built in 1180 by Henry II. But building it had nothing to do with defending Britain's shores; the story behind its vastly expensive construction is one of royal embarrassment and political prestige. It was the Millennium Dome of its day: vast, ridiculously expensive and built to show off the best we can offer. It looks like a quintessentially English castle, but is nothing of the sort; it's French to its foundations. It provides a fascinating insight into the medieval world. For years now, the castle has been empty, grey and dull: a shadow of its former self. But in 2008 English Heritage decided to undertake an extraordinarily bold piece of restoration. They planned to make over the main rooms of the castle to recreate them as they would have been in Henry II's time. It was a huge, ambitious project, bringing together historians, designers and around 150 craftsmen.