As one might expect from such a vast area, its topography is one of contrasts. It ranges from the flat and marginal farmlands of Stormont, Dundas and Glengarry to the rugged forest terrain found in northern Renfrew County. Along the St. Lawrence River and Lake Ontario, the land is lush and rolling and given to profitable cash crops. From a geological perspective, the region contrasts deep deposits sandy and clay loam with the glacial till and shallow soil of the Precambrian Shield which extends from west of the Brockville area north through Lanark County, on to Renfrew and beyond. Further west around Kingston, the huge deposits of sedimentary rock, common to the eastern portion of the region are easily visible.
Mining is limited to predominantly limestone quarry operations in various sectors of the region.
The southern portion of the region, from the Quebec border to Port Hope and ranging 90 km north making an elongated rectangle, is known for its arable lands. It has a mix of dairy and cash crop farms with thousands of hectares given to corn and soy bean. Prince Edward County, in particular produces a broad range of cash crops and a food processing plant. The region is also rich in apple orchards. They are a major producer of a wide variety of apples, the most notable being the world famous McIntosh, which was discovered in 1811 in the hamlet of Dundela in Dundas County.