The unforgettable silhouette of Eilean Donan Castle at the confluence of three sea lochs in the Highlands, seen against the majestic backdrop of the mountains of Kintail, is an iconic image of Scotland and of Scottish history that adorns calendars, shortbread tins and whisky bottles worldwide. Not many people realise that the castle was only built in 1932. Along with Lutyens's slightly better known Lindisfarne of 1906, and Castle Drogo of 1930, it represents the astonishing survival of a nostalgia for the middle ages well into our own lifetimes. This book is the first to investigate and illustrate the phenomenon. These castles were not only (relatively) modest country houses in remote and rugged areas, but some were also colossal and fabulously expensive re-creations of complete medieval complexes like Herstmonceux, Leeds, Hever, Saltwood and Allington in Kent and Sussex, specifically chosen for their proximity and ease of commuting access to London. And beyond the conventional extravagance of the millionaire (often spending the money of his American wife) there were the demented fantasies of the likes of William Randolph Hearst whose St Donat's in Wales boasted thirty bathrooms and a swimming pool with underwater lighting, and or Gordon Selfridge's Hengistbury with its proposed 300 bedroom suites and a tower as high as St Paul's. Amid all these extraordinary fantasies, and the almost equally extraordinary stories associated with them, however, is a more serious narrative about the conservation and restoration of historic monuments. And, at the end of the twentieth century, when the conservation battles have been more or less resolved, again there is an almost incredible resurgence of neo-medievalism with brand-new castles being built in England, Scotland and Wales, often against substantial opposition, but undoubtedly resulting in remarkable and impressive structures. This book tells their story.