Second are the plains, which includes the Saint Lawrence Lowlands, which run from east to west and covers the northern portion of the Montmagny RCM, and is characterized by its arable soils.

A series of peaks and ledges can be found here, and the Notre Dame Mountains dominate its landscape, which can reach an altitude of up to 850 metres (2,790 ft).

Forestry dominates the southern part of the RCM, which houses several primary industries, a sparse density, and limited arable land.

[citation needed] Generally speaking, the primary activity in the northern part of the RCM is agriculture, while forestry dominates the south.

[citation needed] The majority of the businesses can be found along a straight line, several kilometres long, on the Saint Lawrence River (Route 132) and along the Trans-Canada Highway.

The other part of the region, which is almost 80% of the area, wherein the main activities are forestry, the gathering of raw materials related to wood, and services, is located in the Appalachians.