In mountaineering, the six great north faces of the Alps (also called the six 'classic north faces') are known for their difficulty and great height. They are:
Attaining the first ascent of each of these six faces was a major preoccupation of the best European climbers in the 1930s. Gaston Rébuffat, a Chamonix mountain guide and renowned French alpinist, was the first to climb all six of these north faces. His 1954 work, Etoiles et Tempêtes (Starlight and Storm), chronicles these climbs.
Three of these north faces—the Eiger, the Matterhorn and the Grandes Jorasses—are considerably harder to climb than the others. This led to their becoming known as 'the Trilogy'. The first to climb these three faces within a year was the Austrian Leo Schlömmer, from the summer of 1961 to the summer of 1962. Ivano Ghirardini was the first to climb the Trilogy in winter, solo (1977-78). With the introduction of the concept of enchainment, the race was on to climb all three faces in one outing, a race eventually won by Christophe Profit who achieved the feat between 11–12 March 1987 in a time of 24 hours.