On 24 July 1938, with Anderl Heckmair, Ludwig Vörg and Heinrich Harrer, he made the first ascent of the north face of the Eiger. This climb, previously deemed impossible and described by Reinhold Messner as a glorious moment in the history of mountaineering and a great sensation, since several climbers had previously perished on the face, made headlines around the world and is recounted in Heinrich Harrer's 1958 book, The White Spider.