From Mount Wiki
|Elevation|| 4,228 m13,871.391 ft |
|Prominence|| 165 m0.103 miles |
|Location|| Valais, Switzerland|
Valle d'Aosta, Italy
|DMS Coor.||45°55´20"N, 7°47´34"E|
|Swiss Coor.||627521 / 85536|
|Links|| Topographic Detail |
Breithorn Central, Breithorn East, Breithorn Gendarme, Breithorn-Liskamm Group, Liskamm West, Mezzalama Hut, Pollux, Quintino Sella Hut, Roccia Nera, Rossi and Volante Bivouac, Valle d'Ayas Guides' Hut
 General information
Castor (Italian: Castore) (4,228 m) is a mountain in the Pennine Alps on the border between Valais, Switzerland and the Aosta Valley in Italy. It is the higher of a pair of twin peaks (Zwillinge), the other being Pollux, named after the Gemini twins of Roman mythology. Castor lies between Breithorn and Monte Rosa and behind Lyskamm. It is separated from Pollux by a pass at 3,845 m (12,615 ft), named Passo di Verra in Italian and Zwillingsjoch in German.
There is a danger of avalanche depending on snow conditions but mostly one has to watch out for the large number of other climbers. It is a very popular climb for guides with beginners so the summit can have upwards of 100+ people on it.
Castor and Pollux are also a pair of summits in Yellowstone National Park in Wyoming, USA. Located in the Absaroka Range, Castor is 3,308 m, 65 m lower than its twin.
 Climbing history
The first ascent (south-west ridge) was done by F. Jacomb and W. Mathews with M. Cruz on 23 Aug. 1861.
The north-west ridge was done by F. Schuster with P. Baumann and P. Mosser on 9 Aug. 1878.
The north flank was first descended by Miss K. Richardson with J. Bich and E. Rey on 10 Aug. 1890 and first ascended by G. Finch and H. Mantel on 16 Aug. 1909. The first ski descent was by C. Cugnetto and F. Ghisafi on 20 July 1987.
The south-west buttress - classic route was first done by C. Fortina with A. Welf on 4 Aug. 1911. The exact line of their ascent is unknown. The described route was first done by E. Marchesini with E. Frachey in 1938. The first winter ascent was by G. Gualco with E. and O. Frachey on 20 Mar. 1955.
The south-west buttress - guides route was established by E. Cavalieri with O. Frachey and L. Colli with A. Favre on 5 Aug. 1970. The first winter ascent was by A. Jaccod and R. Nicco on 6 Jan. 1984.
The dominant twin, most frequently climbed from the Italian side as the direct approach from the N involves a long ascent of the complex Zwillings Glacier. It is only in winter that frequent ascents are made (on skis) from the Swiss side and then via the Felikjoch.
The base of the SW ridge of the mountain is formed by a massive rock buttress (below Pt. 3,992 m) which separates the Piccolo Verra Glacier and the Castor Glacier. A cairn marks the top of the buttress and a little NE of this is a snow shoulder, known as the Colle del Castore, 3,980 m. This 'col' provides a passage between the Theodulpass and the Quintino Sella Hut section of the Italian Haute Route that avoids the traverse of the Castor. This passage should not be attempted in the afternoon and the slopes on either side can be icy at any time. The buttress itself has a W and a S flank and it is the latter which provides two worthwhile climbs.
 South-East Ridge
The normal route and a pleasant climb from the Quintino Sella Hut. The climb starts at the Felikjoch, which can also be reached from the Monte Rosa Hut or from Liskamm, which is the usual approach when traversing the 4,000 m peaks in the region.
 South-East Ridge from the Quintino Sella Hut (F)
 South-East Ridge from the Monte Rosa Hut (PD)
 South-West Buttress - Guides Route (D+)
 South-West Buttress - Classic Route (D+)
 West-North-West Flank (PD)
 North-West Ridge (PD)
 North Flank (AD)
|Route Name||Hei.||Dif.||Dur. (h)||Type||Rock||°||Valley||Hut||S. Gain||Maps|
Hei.:Height, Dif.: Difficulty, Dur.: Duration, S. Gain: Meters from hut to summit
Summit map is always listed first. If a map is used for 2 km and another map for 1 km, the 2 km map will be listed before the 1 km map. Overview of the Swiss maps & Italian maps.