 The most populous physiographic region is the Saint Lawrence Lowland.It extends northeastward from the southwestern portion of the province along the shores of the Saint Lawrence River to the Quebec City region, limited to the North by the Laurentian Mountains and to the South by the Appalachians.It mainly covers the areas of the Centre-du-Québec, Laval, Montérégie and Montreal, the southern regions of the Capitale-Nationale, Lanaudière, Laurentides, Mauricie and includes Anticosti Island, the Mingan Archipelago, and other small islands of the Gulf of St. Lawrence lowland forests ecoregion.