As repositories of myth and fantasy the Druids are second only to the hypothetical denizens of Atlantis in the popular mind. Piggott, noted archaeologist at the University of Edinburgh, takes a rather sour view of the white-robed processionals that today visit Stonehenge and continually contrasts ""Druids-as-known"" with ""Druids-as-wished-for"" in the romantic imagination. His tripartite study looks first at the archaeological evidence which includes weaponry, tools, fortification techniques and burial sites; second, at the Greek and Latin testimonia, notably Posidonius, the chief Latin source and proponent of what Piggott terms ""hard primitivism,"" as well as the hero-tales and wonder stories in Old Irish and the commentaries of Alexandrine writers who succumbed to ""soft primitivism."" The last section of the book is devoted to the encrustations of legend and folklore which have been going strong since the 18th century. The picture which emerges from Piggott's rather austere presentation is of a heroic society with highly developed and beautifully decorated metal-work, ""conditional literacy,"" a warrior elite, and an itinerant, intertribal learned class which in Ireland if not Gaul, functioned as ""the only national institution."" Piggott concedes, rather disgustedly, that Noble Savage/Golden Age images have clung to the Celts and their priestly class at least since Roman times. In fact, he believes they don't deserve their reputation as benevolent paragons of wisdom and morality: they practiced head-hunting and human sacrifice--a fact Piggott keeps pushing under the reader's nose. The beautiful illustrations of ancient ceremonial grounds, elaborately decorated jewelry and artifacts add a great deal to the lucid incisive text, which however does less to demystify the pre-Christian Celts than Piggott might have wished.