Arnold Durig (1872-1961) grew up in the Austrian mountains in the period when intense exploration of the Alps started. As an enthusiastic mountaineer, scientist, and physician, he became one of the pioneers exploring physiological and pathophysiological aspects of humans sojourning to high altitudes. At the beginning of the 20(th) century, Durig was one of the great physiologists whose knowledge covered the whole field of physiology. Durig founded a renowned School and his students spread all over the world. He stayed in close contact with many colleagues and famous scientists, such as Albert Einstein and Sigmund Freud. Although he was an extremely productive and acknowledged physiologist and teacher at that time, his work and life are not very well known at the beginning of the 3(rd) millennium, even by high altitude physiologists. Thus, this article provides an overview on Durig's life and work, highlighting the most important scientific studies he performed at moderate and high altitudes, in an attempt to provide a few links to the development of high altitude research in the late 19(th) and early 20(th) centuries, complemented by some comments from a current point of view.