This book contains the diary that Achille Compagnoni wrote in 1954 when he took part in the Italian expedition to K2, and which was originally published in 1958 along with additional material by Compagnoni, which is also included in this edition. These were the years of the conquest of the Himalayan peaks by the Western nations. It seemed almost natural that the Italians would be entrusted with the 8616m of K2, because of the tradition that linked Italian explorers to this great peak. The expedition led by Ardito Desio culminated with Achille Compagnoni and Lino Lacedelli on the summit of K2 in the late afternoon of 31st July. This book - and even more, the exhibition mounted at the Museo Nazionale della Scienza e della Tecnologia "Leonardo da Vinci" in Milan, for which the book was printed - does not, however, concentrate only on K2. Its purpose is to recount, through photographs, videos, documents and equipment, the life of Achille Compagnoni on the centenary of the birth of this "astronaut of the peaks", as Salvatore Maria Righi dubbed him.