The Grand Combin is a mountain in the western Pennine Alps in Switzerland. With its 4,314 metres (14,154 ft) high summit it is one of the highest peaks in the Alps and the second most prominent of its range. The Grand Combin is also a large glaciated massif consisting of several summits, among which three are above 4000 metres.
The normal route starts from the Panossière Hut, which lies on the north side in the Corbassière valley. Despite the fact that no major difficulties exist, a particularly dangerous passage has to be traversed on the north flank: Le Corridor. It is a couloir dominated by seracs continuously falling on it.
The massif of the Grand Combin lies south of Verbier between the Val d'Entremont (west) and Val de Bagnes (west). The north-western facing side of Grand Combin is entirely covered by eternal snows and glaciers which are prone to serac falls. The southern and eastern walls are more steep and thus exempt of snow. The topography of the Grand Combin is intricate. Between the Val d'Entremont and the Val de Bagnes are two high ridges, nearly parallel to each other and to those valleys, which both diverge from a short transverse ridge of great height.
The southern end of the space enclosed between these three ridges is an elevated plateau of great extent, where the snows accumulate and feed the Corbassière Glacier which descends thence for about ten kilometers to the north. The glacier is surrounded by the peaks of Petit Combin, Combin de Corbassière and Combin de Boveire on the west, Grand Tavé and Tournelon Blanc on the east. Smaller glaciers lie on the external flanks such as Boveire and Mont Durand Glacier.