With its 5.9 km-long tongue (in 2002), the Glacier Blanc is the longest glacier in the Massif des Écrins and the largest in the southern French Alps. Its area of 5.34 km² (2002) is not, however, as great as that of the Glacier de la Girose and the Glacier du Mont-de-Lans, which form a common system. The Glacier Blanc is a typical valley glacier, which initially runs in a curve towards the northeast below the Barre, before its tongue turns southeast, becoming an icefall. Its average incline is about 30%, but it is flatter in its central section than on the north slope of the Barre des Écrins or in the icefall of its lower section.