Aguja Guillaumet is a mountain in Santa Cruz Province, Argentina.
Description Aguja Guillaumet is a summit in the Andes. The peak is located 1.5 kilometers (0.93 miles) northeast of Fitz Roy and 13 kilometers (8 miles) northwest of El Chaltén, in Los Glaciares National Park of Patagonia. Precipitation runoff from the mountain's slopes drains to Viedma Lake. Topographic relief is significant as the summit rises 1,925 meters (6,315 ft) above Laguna Piedras Blancas in four kilometers (2.5 miles), and 1,175 meters (3,855 ft) above the North Fitz Roy Glacier in one kilometer (0.6 mi). The first ascent of the summit was made in 1965 by Carlos Comesaña and José Luis Fonrouge.Aguja Guillaumet (2539 m.), Andeshandbook.org, Retrieved January 21, 2026. The toponym, which translates as Guillaumet Needle, was applied by Louis Lliboutry in 1952 to honor Henri Guillaumet (1902–1940), a French aviator who carried mail between Argentina and Chile.Lliboutry, Louis. Le Massif du Fitz Roy: Carte au 1:50 000. Expédition Française au Fitz Roy, 1953.Mountain Toponyms., PATAclimb.com, Retrieved January 21, 2026. The nearest higher peak is Aguja Mermoz, 0.475 kilometer (0.3 mile) to the southwest.
Climbing Established climbing routes with first ascents:Aguja Gillaumet Rock Climbing, Mountainproject.com, Retrieved January 21, 2026.
Original route – 1965 – – Carlos Comesaña, José Luis Fonrouge Amy-Vidailhet – 1968 – – Bernard Amy, Pierre Vidailhet Guillot-Conqueugniot – 1968 – – Joël Coqueugniot, François Guillot North Ridge – 1981 – Eduardo Brenner, Eduardo MoschioniAguja Guillaumet, Patagonia, Planetmountain.com, Retrieved January 21, 2026. Hard Sayin’ Not Knowing – 2009 – Kate Rutherford, Michael SchaeferSouth America, Argentina and Chile, Southern Patagonia, Aguja Guillaumet, Hard Sayin' Not Knowing, publications.americanalpineclub.org, Retrieved January 21, 2026. Patagonian Werewolfs – 2012 – Marcos Costa, Sergey DashkevitchSouth America, Argentina, Southern Patagonia, Chalten Massif, Aguja Guillaumet (2,579m), West Face, Patagonian Werewolfs, publications.americanalpineclub.org, Retrieved January 21, 2026.
Climate According to the Köppen climate classification system, Aguja Guillaumet is located in a tundra climate zone with cold, snowy winters, and cool summers. Weather systems are forced upward by the mountains (orographic lift), causing moisture to drop in the form of rain and snow. This climate supports the Piedras Blancas Glacier below the east slope of the peak and the North Fitz Roy Glacier to the west. The months of November through March offer the most favorable weather for visiting or climbing in this area.When is the Best Time to Visit Patagonia?, Wildernesstravel.com, Retrieved January 21, 2026.
Gallery
See also List of mountains in Argentina
References
External links Weather forecast: Aguja Guillaumet Aguja Guillaumet (photo): Pataclimb.com