As commonly used, the term "megaliths" refers to huge, free-standing, neolithic stones whose origin and meaning have long been debated by archaeologists and students of prehistory. Perhaps the most famous neolithic site is Stonehenge, the great circle of giant stones on Salisbury Plain in England. Twentieth-century studies of Stonehenge and other megalithic monuments have given rise to the science of astra-archaeology, i.e, the study of early astronomical knowledge through the interpretation of ancient monuments and other archaeological data. The present volume, by a noted British astronomer, provides a unique introduction to this fascinating discipline. The heart of the book is devoted to a detailed study of Stonehenge (six chapters alone), along with scores of equally mysterious megalithic rings and earthworks scattered throughout the British Isles and northwestern France. Enhanced with more than 140 photos, maps, and illustrations, the text examines Stone Age sculpture, astronomical computations, radiocarbon elating, Egyptian pyramidology, Druidic and other folklore, and many other aspects of the topic. Impartial, painstakingly researched, and lucidly written, the text is an "essential summary of astronomy in the Stone Age" (New Scientist) and a "fascinating, up-to-date sourcebook for the layperson and specialist." (Publishers Weekly). Prologue. Introduction. Notes. References. Bibliography. Index. 142 black-and-white illustrations.