This book by Alton Byers is a first-rate example of repeat photography, and the photographs demonstrate excellent reproduction. Even the nearly 70-year-old enlargements acquired from contact prints of 35-mm negatives appear remarkably clear (it was necessary to use the prints of the negatives because the negatives themselves were lost). His own replicas are outstanding, especially considering that taking them required many thousands of meters of climbing, even serious mountaineering, in search of the exact locations from which the historic photographs had been taken, as far back as the 1950s. The book presents a total of 133 photographs, many of them panoramas, covering the fields of anthropology, human geography, landscape change, and glaciology. This leads into assessment of the impacts of the massive increase in trekking tourism and mountaineering, together with the effects of current climate warming. It follows that the photographic collection is of vital importance as a historical document.

Byers introduces us, through their photography, to many of the early pioneers of mountaineering and survey in the Khumbu. They include John Hunt, Charles Evans, Fritz Muller, Erwin Schneider, Helmut Heuberger, and Charles Houston. The list continues on to anthropologists and foresters, some of whom are known to have published highly contentious claims of post-1950 severe deforestation. These “activists” used dire, yet improbable, claims of landscape despoliation in order to urge government action to establish the Sagarmatha (Mt Everest) National Park and World Heritage Site designation. In this context alone, Byers's record is vital historically, the more so when he considers the recent impacts of climate warming. The misleading claims of massive deforestation are climaxed by a now well-known assertion that a hillslope that was densely forested in 1957 was bare of trees some 2 decades later. In fact, Byers has shown photographically that the same hillslope was devoid of trees long before 1957.

More recent fieldwork by Byers goes on to demonstrate his significant contribution to working with the local community to ensure that Sagarmatha National Park is moving from a disreputable tourist/mountaineer garbage dump to one of the cleanest national parks and World Heritage Sites in existence. To help achieve this he has made an important personal contribution by working with the local Sherpas, not only to effect the cleanup, but also to encourage them to collaborate with visiting specialists and so ensure that they take a leading role in protection against the hazards of possible glacial lake outburst floods. His virtually lifelong commitment to the Khumbu and its people constitutes a vital contribution to one of the main principles outlined in Chapter 13 of Agenda 21 (adopted at the 1992 Rio Earth Summit; United Nations 1992)—to ensure a thorough collaboration between the local mountain people and visiting supporters toward sustainable mountain development.