The Pin River flows successively, in the MRC of: The main neighboring watersheds of the rivière au Pin are: The rivière au Pin has its source at Sunday Lake (length: 2.5 kilometres (1.6 mi); altitude: 367 metres (1,204 ft)) in the municipality of Saints-Martyrs-Canadiens.

This confluence is located in a marsh area, at 1.5 kilometres (0.93 mi) upstream of the Stater Pond (which the Bécancour River partly crosses), at 1.5 kilometres (0.93 mi) southwest of Cranberry hamlet and 1.7 kilometres (1.1 mi) east of the summit of Mont Dillon.

Logging, in particular the essence of pine, contributed to the colonization of the region of Appalachians.

The Rivière aux Pins appears on an 1883 cadastral map of the canton of Ireland.

[2] The toponym Rivière au Pin was made official on December 5, 1968, at the Commission de toponymie du Québec.