The Ojos del Salado (6893 m asl., Chile/Argentina) is the highest volcano on Earth, but it is far from being the only special feature of the very high volcano. It is an extreme location in every sense, as it has the highest wetland on Earth, the highest desert, extreme eolian phenomena, the highest post-volcanic activity, although it is almost 7000 m high, it does not reach the snow line, it is the highest point on Earth reached by vehicle, and is also the site of the highest environmental monitoring on Earth. Continuous instrumental measurements from 4000 m to the top of the mountain in the Dry Andes provide a unique database of the high mountain consequences of climate change. The detailed geoscientific description and analysis of the cold desert of the Puna de Atacama, a giant volcano and its surroundings, also includes microbial life under extreme conditions and even planetary analogies. The book also includes the landscape evolution history of the area, the last glacial reconstructions, the formation of the present-day surface, the characteristics of the hydrological system, the permafrost, the local climate, and the changes in all these. Besides the natural phenomenon and the importance of the location in climate research, the book analyzes the human activities, the challenges and impacts of outdoor tourism and mountaineering in this sensitive environment. By taking us to a typical dry Andean site, it not only provides a comprehensive picture of a mountain and its immediate highland environment, but also gives us an insight into the characteristics of a high Andean mountain belt of some 1000 km.

Balázs Nagy (Hungary) is a geographer, university professor, researcher and mountain guide. His research activity - from the European mountains to Antarctica - focuses on mountain geomorphology, the analyses of the consequences of climate changes. He is active in the popular science journalism and in the adventure tourism industry

Sebastián Ruiz Pereira (Chile) is a researcher in mountain cryosphere with expertise in permafrost hydrology and field investigations. His work focuses on groundwater–permafrost interactions and climate-driven change across the high Andes, southern Patagonia, and Antarctica.