Both the techniques and the scope of air-photography made great advances during the twentieth century. As a result, a mass of material is available to the archaeologist and the local historian. First published in 1982, this was the first comprehensive textbook to explain in detail how to identify archaeological and historical sites from the air. Unavailable for more than ten years, this new edition will be widely welcomed - not least for the addition of a section of colour photographs. Accurate interpretation requires an understanding of the whole landscape. Archaeological sites are not always easily distinguished from geological features or from those produced by agriculture or by industrial, modern military or sporting activities. A wide selection of both archaeological and non-archaeological material is therefore illustrated in the book's 150 air-photographs. Close attention is paid to the nature of the physical remains in the ground and to the processes whereby they can appear on air-photographs. This requires an understanding of these processes - from the turning of the soil to the printing of the photograph. Throughout, the perils of misidentification receive as much consideration as the principles of correct interpretation. The types of site covered in the book are those of the British Isles but the techniques are applicable throughout continental Europe and beyond.