The surface of "Lac aux Montagnais" is usually frozen from the beginning of December to the end of March, however the safe circulation on the ice is generally made from mid-December to mid-March.

A strip of land 1.3 kilometres (0.81 mi) long on the east bank separates it from the Lac de l'Amitié.

On the south shore, their territory included the hydrographic basins of the Rivière du Loup and the Matane River.

Today, permanent installations welcome vacationers, hunters and fishermen to this lake formerly frequented, no doubt, by the Innu in the vicinity of Lac Saint-Jean.

[3] The toponym lac aux Montagnais was formalized on December 5, 1968, by the Commission de toponymie du Québec.